Masters Snooker 2013: Neil Robertson beats Mark Allen Defending champion Neil Robertson beat Mark Allen 6-5 in a gripping Masters quarter-final at Alexandra Palace. The pair shared the first four frames, as Allen knocked in a 138 clearance. A 72 allowed Allen to edge ahead, but the Aussie hit back by winning the next two, including a superb 111 break. The Northern Irishman struck 68 to level at 4-4 and Robertson's 101 put him one away. Allen forced a decider and he laid a snooker, but his opponent escaped, making a century for the win. Robertson will face either Shaun Murphy or John Higgins in Saturday's semi-final. Neil Robertson described his pot on the red from Mark Allen's expertly laid snooker behind the yellow in the decider as one of the finest of his career. There were so many aspects that he had to get right; the correct pace, the right amount of spin, the angle to take the cue ball past the blue. He likened it to a clutch putt on a treacherous green. The defending champion executed it perfectly to launch the clinching century. A great shot worthy of winning a marvellous match. It was fantastic quality throughout. There was some tension in a couple of the frames and I did not think it would get harder after playing Ding [Junhui] but over the moon to get through," Robertson told BBC Sport. You only want one chance in the final frame. I did try to pot the red [after the snooker] and I apologised to Mark after, it is a hard way for him to go out. You don't want to lose in the first round, which happened to me after winning the World Championship, and I have defended titles before which gives me belief that I can do it again. A tremendous battle between the two left-handers was packed with high-quality snooker, as four centuries and five breaks over 60 were compiled. Robertson, 30, now has the chance of becoming only the fourth man to defend the Masters crown after Cliff Thorburn, Stephen Hendry and Paul Hunter. But for Allen, whose 138 break is the highest of the tournament so far, it was a desperate defeat having competed valiantly from start to finish, not seeing himself more than one frame behind at any time. He had gone 60 in front in the crucial 10th frame, missing a red to the centre pocket and Robertson had the chance to launch a counter-attack for victory but failed to capitalise. Allen thought he gained the upper hand after playing a delicate snooker in the last, but saw Robertson escape with a pot on a red, before making 105 to triumph.