Nick Bollettieri's Wimbledon Files: A fifth triumph at SW19 would crown Serena's finest hour This is what says it all about Serena Williams. On Thursday evening, she was on Centre Court, back where a few hours earlier she had blasted past Victoria Azarenka, the No 2 seed, to reach her seventh Wimbledon final. She was out there playing doubles with her sister, and winning again by the way. They are a remarkable family. They are a unit, Venus, Serena and their daddy, Richard. The environment in which they grew up and in which they have lived since has helped the sisters become what they are. They had very little when they were little. They are fighters and they will fight to hold on to their standing on the court to the very end. United they stand and united they will fall. Except there's no sign of Serena falling any time soon. It is remarkable to see her preparing for another Wimbledon final after what she has been through over the last couple of years - she might have lost her life. For those who don't know, she had a pulmonary embolism and a haematoma which obviously could have had severe consequences. Richard said that this is not about winning a tennis match, it's about winning a life. A win this afternoon would stand up there with anything she has achieved on a tennis court. So what's going to happen out there on that grass? Serena is favourite and you can't argue with that. Not with that serve. It is unbelievable that anybody can serve that well. Holy cow, she even sent down a second-serve ace at 90mph in that doubles match. The mph she is clocking is phenomenal. It's by a margin the best in the women's game - and you know what? It's a damn sight better than 60/70 per cent of the guys on the men's tour. She has always had a good serve but right now it is firing better than ever - boom, boom, boom, to 85 aces over her six matches here. It means her opponents have so little margin for error - they cannot afford to miss a single opportunity. But this is by no means a done deal. Agnieszka Radwanska can win this match. She has the tools - she is a dangerous player. She has a good first serve and her second is OK. Her real skill is the ability to mix her defensive game with offence. The balance is there and watch out for her goof balls, the way she changes the pace of a game with a surprise shot. She is a little magician out there, always forcing her opponent to hit an extra ball. Serena's got issues to deal with too. OK so the serve is a huge, huge weapon but I have concerns over other areas of her game and how she is getting around the court. She needs to improve her groundstrokes from the level they have been at so far in the tournament. If the rallies get going it will favour Radwanska. That is one hell of an if - she will first have to find a way to survive the serve, or hope Serena's radar goes down for the day. My other concern for Radwanska is her ability to create her shots if the ball is coming at her with real power. It can make her rush her shots. Serena will be in a rush to finish the match, while Radwanska will look to stretch it and stretch her opponent across the court. The Pole will be pushed out of her comfort zone by Serena's serve and that can make the difference. Today's big match: Serena Williams v Agnieszka Radwanska US Nationality Polish Palm Beach Residence Krakow 5ft 9in Height 5ft 8in 6 World ranking 3 41 Career titles 10 $36m Career prize-money $9m 66-9 Wimbledon record 18-4 Win, 2002/3/9/10 Wimbledon best Final, 2012 1-6 Odds 6-1 Bollettieri's prediction Williams in three Coaching report: Roger Federer v Novak Djokovic Peerless Federer can do anything Let me tell you straight. If Roger Federer wins Wimbledon tomorrow it will, at a stroke my friends, end the argument over who is the best player of all time. He has gone through two lean years since that last Slam win in Australia and when that happens people start to question you. Hey, it's human nature. Yesterday Federer answered a whole lot of questions - he needs that one more win to answer them all - and he was brilliant. Brilliant, brilliant, brilliant. He played magnificently from point one. He has the best forehand the game has seen and he used it to perfect effect. The conditions were in Federer's favour. The roof being shut works better for the Swiss as there no is wind or sun to interfere with his game. The neutral conditions also suit his one-handed backhand. Federer's all-round game is fantastic. He is one of the very few to be able to do a little bit of everything. He can play offence, he can play defence, he can switch to neutral, go back or serve and volley. And he thinks too, the guy is a real smart thinker. Federer did two things against Novak Djokovic. Instead of serving and then volleying he would serve, play a defensive ball and then go in on the volley. He also looked to push Djokovic out wide on his forehand, out to where the courts are still green and it's more difficult to come back from. I was surprised how Djokovic's forehand broke down under pressure and he made more errors on his backhand too. That is unusual for a two-handed backhand against a one-handed one. It was an unusual performance all-round from Djokovic. He hit more defensive returns than you would expect and it seemed like there was a lack of intensity out there. He will be back, no doubt about that but the day belonged to Federer. One other feature of the match struck me: just look how important Hawkeye has become. And it's vital too for players to get their challenges right because they can make a big difference at big moments.