MARK WILLIAMS held off a superb fightback from fellow former winner John Higgins today to triumph in a last-frame decider and reach his eighth World Championship semi-final at the Crucible.

The veteran duo, who have won seven world titles between them, were locked at 8-8 at the end of their second session before Williams put himself on the brink by taking all four frames on today’s resumption.

Four-time champion Higgins, though, dug in following the mid-session interval with breaks of 94, 114 and 67 to force a decider, which Williams took after his opponent missed a tense blue on the top cushion to seal a 13-12 victory.