World Snooker Championship semi-final against Judd Trump - including in his attempts to scare referee Desislava Bozhilova. Three-time world champion Williams is 7-1 behind against Trump after a brutal first session at the Crucible.
But before the scoreboard started to get a little hairy for the Welsh potter, he had a bit of fun with Bozhilova.The Bulgarian official was using all of her concentration to put the pink back on its spot in amongst a crowd of reds when someone inside the Crucible made a loud banging noise.
Bozhilova didn't flinch as the commentary team revealed the culprit to be none other than Williams. The moment went down a storm with the audience inside the Sheffield arena, who burst into laughter.
Bozhilova carried on with the job in hand but raised a little smile as she carefully rolled the pink back into its position. "Yeah, that was Mark Williams banging his cue on the floor," confirmed commentator Joe Johnson. "Trying to frighten her!
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