World number 16 Stephen Lee broke through a physiological barrier last night by reaching the semi-finals of a ranking tournament for the first time. After five previous failures in the last eight, the Wiltshire professional defeated Mark King 9-2 to book a UK Championship showdown on Saturday with Ronnie O'Sullivan or outsider Gerard Greene.

Lee has dropped only four frames in his last two matches and progressed virtually unseen into the last four of the £440,000 event.

Romford left-hander King, who accounted for 1991 UK champion John Parrott in the last 32, never threatened to prevent Lee achieving his long-awaited goal.

Indeed, apart from the scoreline, King, the world number 20, will always remember the match for the wrong reason. In frame five he conceded 48 penalty points from 12 successive misses, a record for a televised game.

With 14 reds to aim for, King stubbornly went for the same ball, trying to escape via two cushions with the cue-ball tucked up tightly behind the green.

Earlier, Welshman Matthew Stevens produced a sparkling display against Scotland's Martin Dziewialtowski to virtually book his passage into the semi-finals.