Snooker: Remarkable shot is escape to victory for Neil Robertson Defending champion Neil Robertson produced an incredible escape shot and converted it into a match-winning century as he saw off Mark Allen in a high-class quarter-final at the Betfair Masters. With the match into a deciding frame, Allen put Robertson in all sorts of trouble when he ran through off a red to tuck in snugly behind the yellow, which was just off its spot. Robertson's only real chance of an escape was to target a red hanging over a top pocket, and Allen could do nothing but watch as his opponent went off the cushion and down to the pocket, clipping in the red and landing on the blaack. From there Australian Robertson made a classy 105 to win the match 6-5, before being congratulated by Allen. You'd get it maybe one in 10 times. I had to apologise to Mark," Robertson said. It's a hard way to go out of the tournament from his point of view. I gave myself a chance to pot it and I'm over the moon to get through. Four of the eight first-round matches at Alexandra Palace went the distance, so it was little surprise this one did too, with the pair meeting at the tournament for the third successive year. Robertson drew first blood, making a frame-winning 66 after Allen had to stretch too far to make a red into the green pocket, but the Northern Irishman quickly made it 1-1. Allen landed a long-range red in the next, but broke down on 13, leaving Robertson to make a clinching 73 that was started by a plant. Allen roared back with a brilliant 138 - the highest break of the tournament - and he edged ahead with a 72 in the fifth frame before Robertson responded with 111 to lead 4-3. Four-all duly followed and the pattern continued, with Robertson 5-4 ahead after a 101 off a plant and Allen levelling. Robertson's wonder shot gave him the first chance in the decider and last year's winner did not look back as he went through to the semi-finals. Robertson had come from 5-3 down to beat Ding Junhui in the first round and, in his next match on Saturday afternoon, will face the winner of tonight's quarter-final between John Higgins and Shaun Murphy. "It won't get any easier," Robertson said. World Snooker have made it as hard as possible for me, just like last year, but I think it's probably what brings the best out of me. Robertson, the 2010 world champion, is having a decent season, but has yet to claim a major title and hopes to rectify that on Sunday. He said: "I haven't won a big one yet but this is a chance. I'm in the semis now and there's only going to be four people left.