Judd Trump punished a series of costly errors from Mark Williams to build a 5-3 lead in their World Snooker Championship semi-final at the Crucible. A tense start to the match was filled with mistakes and it was a missed routine black by Williams in the eighth frame that enabled Trump to establish a healthy overnight advantage.

SHEFFIELD, England (Reuters) -Welshman Mark Williams rolled back the years and advanced to the world championship final by defeating world number one Judd Trump 17-14 at the Crucible on Saturday, with the 50-year old becoming the oldest player to reach the decider.