Mark Williams leaves Crucible crowd in stitches with sarcastic comment towards referee during World Snooker Championship final

Mark Williams caused laughter among the crowd at the Crucible during the opening exchanges of the World Snooker Championship final.

The Welshman is taking on Chinese star Zhao Xintong after becoming the oldest player ever, at 50, to reach a Crucible final.

Williams defeated Judd Trump 17-14 in his semi-final, while Xintong thrashed Ronnie O'Sullivan 17-7.

Xintong is officially listed an amateur, having recently returned to the sport after serving a ban of more than two years.

He was one of 10 Chinese players involved in a match-fixing scandal back in 2022, though received a lesser ban to the other players as he was the only one not to be directly involved in fixing or conspiring to fix a match.

Instead, Xintong accepted a charge of being a party to another player fixing two matches (being aware of a match being fixed) and betting on matches.

Prior to his ban, the 28-year-old was a consistent top 16 player and tipped to be a future world champion, and has already secured his position back among the elite for next season after winning the Q Tour.

On Sunday afternoon, Xintong raced into a 3-1 lead over Williams, continuing the imperious form that saw him demolish seven-time champion O'Sullivan.

During the fifth frame, Williams found himself snookered on all six colours, with referee Desislava Bozhilova asking him to nominate which colour he would be aiming for.

The Welshman mouthed 'yellow' to the referee before changing his answer to black as he got down to the shot, causing a ripple of laughter among the crowd in Sheffield.

BBC commentator Dennis Taylor jokingly warned Williams to 'be careful', while TNT Sports' Neal Foulds said: "He's being sarcastic - I'm not sure he can get away with that!"

Thankfully for the Welshman, he did manage to hit the black - as a failure to do so would have awarded Xintong four points.

But the Chinese star took all four of the remaining frames to take a huge 7-1 lead in the best-of-35 frame final.

Should Xintong get over the winning line, he will become China's first world champion, and the first amateur to win the World Snooker Championship.

After his semi-final win over O'Sullivan, the 28-year-old thanked 'The Rocket' for mentoring him throughout his early days in the sport.

"I can't believe it," he admitted to BBC Sport. "Thank you to Ronnie, he helped me a lot before. He's my idol."