Andy Murray v Roger Federer: live 12.44 *Federer 4-6, 7-6, 3-6, 7-6, 2-6 Murray A loose game here from Federer who brings his unforced errors count up to 59 for the match now. Murray brings up two match points when he swipes at a forehand and there's no way Federer can chase that down. Murray is denied the first but when Federer hits a long forehand the match, Murray has done it. His first win over Federer at a grand slam. 12.41 Federer 4-6, 7-6, 3-6, 7-6, 2-5 Murray* A 20th ace of the match and Murray is in full cruise control. Oh wait, make that 21 as he brings up two game points. I don't think he's served better against Federer than he has tonight, potentially against him in the Olympics final, but certainly never in a slam. 12.38 *Federer 4-6, 7-6, 3-6, 7-6, 2-4 Murray Murray stands still on the baseline as he waits for Federer to make his move at the net and he cheekily pushes the ball back for 40-love. An easy hold but Murray looked to be conserving his energy there. 12.35 Federer 4-6, 7-6, 3-6, 7-6, 1-4 Murray* It's comfortable again on serve for Murray out there, disguising a great backhand winner to move 40-love up. Federer's not getting a look in on his serve again. He brutally dispatches a forehand winner which whizzes past Federer on the baseline. One-way traffic now. 12.32 *Federer 4-6, 7-6, 3-6, 7-6, 1-3 Murray Love the fact that John Lloyd and Andrew Castle are having a big debate on how many bananas Murray has eaten during this match with Castle even asking at one point: is it a fruit? Fatigue clearly getting to the BBC commentator. Anyway, bananas aside and Federer is beginning to look a beaten man as he struggles to make inroads into the decider. Murray attempts to pass an advancing Federer at 30-all but he can't get enough on his return. Another unforced error after deuce and Federer is finally on the board. 12.27 Federer 4-6, 7-6, 3-6, 7-6, 0-3 Murray* Murray has rediscovered his form from the first set, getting his first serves in and containing Federer with ease. He cements the break to love when Federer attempts a drop shot, but it's a tired effort and it flops into the net. 12.25 *Federer 4-6, 7-6, 3-6, 7-6, 0-2 Murray A couple of misses by Federer brings Murray back to 30-all, his 31 year-old legs perhaps starting to feel it now. Another loose shot presents Murray with an early break-point opening and when Federer skies one, Murray has the break he needed. 12.21 Federer 4-6, 7-6, 3-6, 7-6, 0-1 Murray* Just how Murray has been affected mentality having failed to serve out for the match remains to be seen but his energy levels won't be in doubt. He hangs in to get an early lead in the fifth as he holds to 30. Federer went five sets with Tsonga on Wednesday, although that did take about three and a half hours. The Swiss has shown signs of fatigue tonight and even if he comes through this clash, how would he fare against marathon-man Djokovic? 12.15 *Federer 4-6, 7-6, 3-6, 7-6 Murray Tie-break: no need to ask who the crowd want to see win this tie-break as roar after roar go up as Federer inches ever closer to back-to-back five setters by edging 2-0 up. Incidentally Federer has never won successive five-setters in his grand slam career. Murray draws him back at two-all. Just like the tie-break in the second set, Murray is distracted by a noise from the crowd, and he's chasing at shadows again as he falls 4-2 down and to add insult to injury a string goes on his racket. Federer punishes a Murray second serve to move to within two points of the set and has four set points when Murray goes long. It's into a decider when Murray can't return. 12.08 Federer 4-6, 7-6, 3-6, 6-6 Murray* Some deep-hitting from Federer but Murray is equal to the Swiss and passes him with a forehand drive. Federer makes some remark towards Murray which the Scot smirks at. Would love to know what he said but the moment has gone and both men put their game faces back on. A strong first serve puts Murray to within two points of a place in Sunday's final. Federer shows some resolve to hang in a point after managing to get something on another powerful serve down the T. And Federer won't go quietly as he delivers an amazing backhand for a break-point chance. And what's this. Murray flashes and misses a forehand after Federer quite simply gets another cracking return in. Murray whacks out at the ball. 12.01 *Federer 4-6, 7-6, 3-6, 5-6 Murray Murray steals an early march in the 11th game of the fourth at 30-love up. Federer is forced to go long again as Murray sets up three game points. Oooh, it's tense out there now. And he wins a fourth straight point to seal the break when Federer makes another unforced error. All Murray has to do is serve out another game, it's as simple as that, surely? 11.58 Federer 4-6, 7-6, 3-6, 5-5 Murray* That's just what Murray needed after a topsy-turvy last service game as he denies Federer of breaking to take the fourth set with a hold to love. 11.54 *Federer 4-6, 7-6, 3-6, 5-4 Murray Over three hours on court now and it's hard to call which way this match is going to swing next. Murray fails to get a second serve back in the court and he knows he's let Federer off the hook. But wait, Federer drags at one to bring Murray in to deuce. Federer lands his next forehand, although it may have gone long but Murray is out of challenges and can't do anything about it. We don't get to see a replay either, no matter, the game has gone. 11.49 Federer 4-6, 7-6, 3-6, 4-4 Murray* Murray is storming the ace count as his sends down his 18th compared to Federer's measly five. A couple of clips to the net cord go Federer's way for 30-all and he has another break point opening when he flashes a backhand winner which clips the line. Federer goes for it, but over-eggs his forehand to give Murray a let-off. Federer has the crowd rocking again when he powers home a forehand for deuce but Murray responds in sublime fashion with his own controlled backhand winner down the line. Federer goes long on the next point but wait there's controversy as a line-judge over-rules a call of out and both men are angered that they have to replay the point. No worries as Murray responds with a strong first serve but a fourth deuce later and Murray eventually holds. Got him. Warne took a catch during the fourth set. Really, he did 11.37 *Federer 4-6, 7-6, 3-6, 4-3 Murray Now Federer has a wobble on his serve as nerves get to both men. Federer can't make a pick up as he comes to net and Murray now has a break point. He pins Federer back behind the baseline and he's back in this set. 11.34 Federer 4-6, 7-6, 3-6, 4-2 Murray* Great response from Murray as he stays in the set with a comfortable hold to 15. 11.30 *Federer 4-6, 7-6, 3-6, 4-1 Murray Federer has been energised by that lack of concentration from Murray and the crowd let out a mighty roar as he surges 40-love up with a confident forehand winner. Murray is briefly let in when Federer goes long but cements the break on the next. 11.27 Federer 4-6, 7-6, 3-6, 3-1 Murray* A couple of loose strokes from Murray and some angry muttering later and the Scot is staring at 30-love down. He chips and charges but a long return gives Federer three break points for the first time in the match. What was I saying? Murray saves the first with a timely first serve and saves the next with an outswinging first serve. He can't save a third as he pulls his forehand wide. 11.22 *Federer 4-6, 7-6, 3-6, 2-1 Murray A stronger service game for Federer as Murray's energy levels dip slightly. Murray still has the edge overall but he'll have to be careful not to give Federer an inch on his serve. Graham Temple on Murray-Fed rivalry: It can't really be called the best rivalry yet because he has always won the Grand Slam meetings. (interesting how Federer is automatically "he" - not quite he who must not be named, but without question the master to date). However it is clearly changing of the guard and Murray could be on to a first GS win (against the Fed) tonight. It would be ironic if Fed won them all up to now and AM all henceforth as I am sure they will have a few more GS meetings yet. 11.19 Federer 4-6, 7-6, 3-6, 1-1 Murray* Murray wasn't affected by that slip up in the last game as he chases down a short return but Federer pounces at the net to leave Murray wondering why he bothered. Murray is giving Federer a look at a few second serves here, but an outswinging forehand return gives his game point and a similiar winner on the next gives him game. 11.13 *Federer 4-6, 7-6, 3-6, 1-0 Murray After a lengthy rest break from both players it's Murray who settles back into his groove and Federer looks pretty knackered out there, which is a rareity. He moves to break point when Federer hits a loose return but Murray can't take advantage as he slips as he shifts his body weight trying to chase another shot down. A second deuce later and Federer is on the board. Alexander Agranovsky on tennis rivalries: I don't believe in players having more than one real rival in their career. After the dust settled on Sampras and Agassi era, nobody remembers that both of them used to have difficult time and competitive head-to-head records with guys like Jim Courier, Michael Chang etc - they will be forever paired as part of the rivalry in our minds. Same goes for Becker and Edberg, Borg and McEnroe. Roger's rival has always been and will forever remain Rafa Nadal - and with Rafa out and Roger in decline, this is no longer the biggest rivalry in sport. Which leaves two top players which look like they are destined to carve a rivalry of their own - Andy Murray and Novak Djokovic. For the moment, it's still slightly too one-sided in Nole's favour, and you really need to be a multiple major winner to be considered a part of historic rivalry - but if Andy wins on Sunday, we might be in for something special. 11.04 Federer 4-6, 7-6, 3-6 Murray* Federer is still struggling to get into a winning position when he goes toe-to-toe with Murray and the Brit brings up two set points when he flashes an inch-perfect winner inside the baseline. He takes the set in 36 minutes with another ace down the T. MURRAY WINS THIRD SET TO EDGE 2-1 UP 11.01 *Federer 4-6, 7-6, 3-5 Murray Murray being slightly casual in this game, deciding not to chase everything down and maybe preferring to conserve his energy and serve out the set instead. Saying that he is lured into one rally and forces Federer to go long for 40-30 but finds the net on the next point. 10.57 Federer 4-6, 7-6, 2-5 Murray* Murray backs up the break in the best possible way with a hold to love. Encouraging signs again from the British No 1 but still tense for his fans out there. 10.55 *Federer 4-6, 7-6, 2-4 Murray Improved signs from Murray here as he moves a mini-break up and now it's Federer's turn to mutter something towards the umpire as he falls three break points down. This is very unlike Federer. He uses his angry energy to good effect to save the first but hits a casual backhand into the tramlines to hand Murray the break. 10.50 Federer 4-6, 7-6, 2-3 Murray* Dead-panned as usual, Ivan Lendl isn't giving anything away in Murray's corner as the Scot pulls at his left thigh muscle. He correctly over-runs another awful line call for 30-15 but a wayward backhand return brings Federer back. Murray's levels are starting to drop here and he's got to be careful not to allow Federer a sniff at a break. Another cry of 'come on' and this time it's a good 'come on' as Federer goes long. A lovely put away gives him game and he needed that. 10.46 *Federer 4-6, 7-6, 2-2 Murray The first cry of 'come on' comes out of Murray's mouth and it's in disgust rather than excitement as Federer works his way to 40-love. He's really grimacing out there on every point now, maybe he is felling a twinge or something's not completely right. 10.42 Federer 4-6, 7-6, 1-2 Murray* Despite sharing a few sarcastic-looking smirks with his corner, Murray mantains his concentration levels and holds to love when Federer finds the tramlines at the end of the longest rally of the game. He mutters something to the umpire as he retreats to his chair, was he asking for the trainer? It seems not, he's fine. 10.39 *Federer 4-6, 7-6, 1-1 Murray A sloppy start to Federer's service game which is uncharacteristic of the 17-time grand slam champ, usually he's all over his opponent but no so today. Murray puts away a volley which was similar to that which he failed to dispatch in the tie-break and that will cheer him for 30-all. Murray gets drawn into another long rally but steps in to one backhand to force Federer to go wide and that's a first break point opening of the set and for a long time. He's pegged back to deuce and challenges an ace from Federer on the next but it's flush down the T. Federer holds when Murray drags the ball low into the net. 10.34 Federer 4-6, 7-6, 0-1 Murray* A change of the shirt later and Murray has wiped that tie-break from his memory and is back on song with his serve, winning it to 30 with a backhand cross-court winner. 10.29 Federer 4-6, 7-6 Murray Tie-break: Two wild forehands from Murray gift Federer an early advantage at 2-1 off his serve and Federer swats away a volley for a 4-1 lead. This is Fed's fifth tie-break of the tournament and only Murray's first but the British No 1 is still to drop a set this fortnight. The two men guzzle some water at the changeover as Murray serves trailing 4-2. A noise in the crowd distracts him momentarily but he correctly challenges a bad line call and is back level when Federer finds the net. It's nip and tuck out there and for the first time Murray looks anxious as he falls 5-4 down. He goes back on the attack rushing to net but can't get enough on his next volley at the net as Federer passes him for 6-5 and Murray rubs his forehead. Murray strikes long and Federer takes it. Murray will rue that point at 5-all, he should have dispatched that volley but was really stretching to make the return. 10.19 Federer 4-6, 6-6 Murray* Murray was sublime in his win over Jeremy Chardy in the quarters and he's taken that form into tonight's clash. The Brit is wrongfooted by a classic forehand winner from Federer but another ace out wide coupled with an ace down the T and we have a tie-break. 10.15 *Federer 4-6, 6-5 Murray Murray attempts to swat at a second serve but his timing is off and Federer holds to love. This is heading to a tie-break but where's your money? Mine's on Murray to edge it and to go on to win the third. Are you with me? 10.13 Federer 4-6, 5-5 Murray* Even when Federer has a look at a second serve, Murray is able to mix up his groundstrokes and work his way into a position to deliver a winner. That's how his game has evolved over the last couple of years, he's not afraid to go for it now. Federer mutters an expletive, yes even the clean-cut Federer resorts to some dirty language from time to time, as he can't get enough on a service return and Murray is back level. 10.07 *Federer 4-6, 5-4 Murray Murray has spent over two hours less time on court this fortnight and it's showing as he charges down a short return from Federer but a wayward backhand presents Federer with two game points. Fed wraps it up on the first. That's back-to-back games he's denied Murray of a glimpse of a break point. Web Masterson on tennis's great rivalry: There's still rivalry between Nadal and Federer; but the top rivalry is between Djokovic and Murray, for world No 1. Watch this space on Sunday? 10.05 Federer 4-6, 4-4 Murray* Federer is starting to find his rhythm on his own service but he's still not getting close to coming up with any answers to Murray's serving. He gets a look at a rare second serve, but even when the two lock horns at the baseline, Murray is edging the duels. 10.01 *Federer 4-6, 4-3 Murray Murray starting to be more vocal now as Federer slowly edges his way back into this match. That won't do the Brit any favours. He manages to pull Federer back to 30 but it's a more comfortable hold as the Swiss varies up his serve. 09.58 Federer 4-6, 3-3 Murray* Murray strikes the tape with a backhand return and it lands inside his court, how dare that ball. Not quite everything is going his way tonight. A long forehand sees Murray slightly jarred for the first time in the match at 30-all but he crucially takes the next point when Federer can't pass an advancing Murray. A booming ace, and Murray quells the danger. Geoff Turner on today's great tennis rivalry: This match generates so much interest as Murray is in the ascendency and the Fed now on the wane. Has he still got the edge? But the rivalry, without Rafa on the scene, has to be between Murray and Djokovic, with so many scores to settle. 09.51 *Federer 4-6, 3-2 Murray Murray scampers up and down the baseline making Federer play one more shot but he can't capitalise on a mini-break as the Swiss pegs him back. Federer shows great resolve to win a 15-stroke rally for advantage but Murray again won't let him off the hook. A second deuce later and his first ace of the contest and we're still on serve. 09.47 Federer 4-6, 2-2 Murray* An hour on court now and if Murray continues to serve in this vein it could be wrapped up in straight sets. Federer can't read Murray's serve and while he's able to execute the odd winner, his unforced errors count is creeping up. Another easy hold for Murray. 09.43 *Federer 4-6, 2-1 Murray Federer is looking far from frustrated or rattled out there and a casual backhand winner is just the tonic he needs if he had any nerves to settle. A hold to 15 and the players retreat to their corners with Murray very much with his tail still up. 09.40 Federer 4-6, 1-1 Murray* Murray delivers his sixth ace of the match as he continues to vary up his first serve and befuddle Federer which isn't an easy task. A game to 15 and it's looking rather comfortable for him at present. 09.37 *Federer 4-6, 1-0 Murray A first double-fault of the night brings Murray back in at deuce and the Brit is making it very difficult for Federer on his first serve with some cracking returns. Federer digs in to keep Murray at bay, needing a full seven minutes to contain him. 09.31 Federer 4-6 Murray* Federer bullies Murray around the court pushing him side-to-side and taking control but further great serving from Murray edges him 30-15 in front. Federer is caught all at sea on the baseline as Murray moves to two set points and he only needs one as Federer can't get his return back. 09.25 *Federer 4-5 Murray Murray's returning is spot-on tonight and Federer is struggling to get into his own rhythm, he holds to 30 but Murray has been dominant this first set. 09.23 Federer 3-5 Murray* Murray is coming out on top from the basline and at the net, showing more ambition and aggressive. A service game to love is just the tonic. Federer is serving to stay in the set. 09.20 *Federer 3-4 Murray An early mini-break for Murray as Federer continues to push long and he races to two break points when he draws Federer to net and passes him with a backhand winner. He can't make the most of the first and is desperately close to pulling off the point of the match when he sticks out his racket head in hope attempting to return a Federer lob and the ball falls agonishingly into the tramlines. Federer overcomes the scare to deny Murray of another break. 09.15 Federer 2-4 Murray* Murray chips and charges to net but Federer needs no second invitation to pass him and it's an easy point on the board for the Swiss. Murray has already accumulated more than double the amount of winners to Federer - impressive stuff from the Brit - and he goes on to hold to 30. 09.10 *Federer 2-3 Murray No wobble from Federer this time as he holds to love. The first game of the match that Murray hasn't picked up a break point opening. 09.07 Federer 1-3 Murray* Strong first serving from Murray as he races to 40-love before a couple of erorrs let Federer back in. Murray loses his footing as he gets caught out by a sliced return but saves a break point with a timely ace. Another strong first serve puts Federer on the backfoot despite his best efforts to lob his rival, but a third deuce later and Murray slam dunks his way to advantage. A body first serve cements the break but only just. Arni Highfield on today's great tennis rivalry: Clearly its the three-way rivalry between Djokovic, Federer and Murray. Currently nobody else comes close, and nobody seriously predicted anybody but one of these three to win in Melbourne. When Nadal was fit, we had four of the finest tennis payers ever seen playing against each other. In other eras there tended to be one or two, and I doubt any from the past but Sampras could have stood against them. 08.59 *Federer 1-2 Murray Federer pins Murray to his backhand, forcing him further and further out wide but Murray gets his returns back with extra, forcing Federer into an error. That's now another two break points to add to the one he picked up in the first. He overcooks the first and finds the net on the next. A perfectly-weighted forehand return loops nicely over the net and floats onto the baseline for a third break point. But Murray is caught out by an injection of speed by Fed and it's back to deuce. No need to panic, in a flash he has a fourth break point, he needs to take this one. Federer misses another first serve and is punished when he can't get a powerful Murray forehand back. 08.52 Federer 1-1 Murray* Murray's first-serve has so often been his weakness when it comes to the big, big matches and Federer is looking to pounce on any short ball. An over-rule brings up a first ace of the match for Murray and he's up and on the board when he takes the next point. 08.49 *Federer 1-0 Murray (*denotes next server) Murray starts with real purpose drilling down a powerful winner on just the second point of the match. That's what he needs to do from the off. The first baseline slug of the contest goes Murray's way when Federer pushes long after a 28-stroke rally to give Murray a first break point. Federer slaps home a volley to bring it back to deuce and has advantage when Murray goes long. A perfectly-weighted outside swinging forehand gives him game. 08.43 Boo to the Federer camp as Mirka wraps a Nike top round the camera to prevent a close up of Mrs Federer. No worries the numerous other cameras can spy on her instead. Here we go then... 08.35 Both players enter the court, Murray might have quite a few supporters as they sun comes down on Rod Laver tonight but no where near as many as Aussie favourite Federer. 08.25 Not just Agassi predicting Murray in four today, lots of you on email think likewise, surprisingly, though, eight of their last nine clashes have been won in straight sets. 08.10 At 31 years-old Federer is the oldest Australian open semi-finalist since Andre Agassi at 33 years back in 2004. So is Andre lending his support to the 'old guy' out there today? I see Murray winning in four. But I'm sort of out of the business of predicting Federer. For half his career he impressed me and surprised me; now he no longer surprises me. He just continues to impress me with what he's able to do. But he's almost 32 years old. Just went through a monster battle with Tsonga heading in against a guy that is going to get him to feel the need to press early, else it's going to be a physical duel. Need a recap on what happened in 2004? Marat Safin beat Agassi in a five-set epic and went on to lose to a certain Mr Federer in the final. 07.55 Here's Murray on why he's failed to get one over Roge in the majors: Maybe I've not converted as many chances as I needed to against Roger in the slams. And that's where his experience has probably told. But I think the match at the Olympics was good for me mentally. To have played him over five sets and to have won quickly and convincingly was good for me. You have to realise that once you get ahead of these guys, you need to stay on top of them. Having been agitated by Murray's style of play in the past, Federer now relishes his match-ups with the Scot: It tends to get very tactical. It has never been a straightforward match. He would make you doubt yourself and play very different to the rest of the guys. Now it's changed a bit because he's playing more offensive. The rallies aren't as long and as gruelling as they used to be. 07.30 Morning and welcome to coverage as Andy Murray aims to break his grand slam duck against Roger Federer. Despite edging their head-to-head record at 10-9, the British No 1 is yet to produce the goods in a major in three attempts: the 2008 US Open, 2010 Australian Open and 2012 Wimbledon final. There have been tears after those two most recent heartbreaking defeats but the Brit is made of sterner stuff these days having notched up a maiden major victory at Flushing Meadows just five months ago. Murray heads into today's clash much fresher having spent less time on court than the world No 2 and without dropping a set this fortnight either. But Federer dispelled any fears he might be tournament-rusty to come through a five-set classic with Jo-Wilfried Tsonga to reach the last two on Wednesday night and, fingers crossed, Rod Laver is set to witness another high-quality match up this evening. It's also Murray's first taste of action under the lights, the tournament organisers not being inspired by the Brit's path into the semis following clashes with Jeremy Chardy, Gilles Simon and Ricardus Berankus. Anyway, let's hear your predictions ahead of tonight's contest with the players due on court at 8.30am. Can Murray finally get one over the elegant Swiss, can he go on to become the first man in the Open era to win back-to-back slams and will he soon be the next world No 1? Email vicki.hodges@telegraph.co.uk