MARK Allen overcame tournament favourite Neil Robertson 6- 4 to seal a semi-final place at the Ladbrokes Mobile Masters.

The match was a curious mixture of classy break-building and scrappy spells, Allen making five half-centuries to his opponent’s four.

But the pair still needed over three hours to complete the 10 frames.

Allen, from Northern Ireland, made a break of 63 then prevailed in a high-quality safety battle to win the opening frame, and also stole the second from 42-0 down with a run of 69.

A wonderful break of 69 to the pink got the Australian on the board in an initially scruffy third frame, and a 56 in the fourth helped him level matters at the mid-session interval.

Robertson went 3-2 ahead with breaks of 47 and 50 in the first frame back before the sixth became bogged down in containing safety play.