Judd Trump’s UK Championship semi-final showdown with Kyren Wilson was momentarily delayed at the start after the Bristol potter noticed something on the cue ball. Trump showed the ball to the referee as he was about to take his break-off shot, and the match official opted to replace it.

The semi-finals have thrown up a mouthwatering encounter, with two of the best players in the world going head-to-head for a place in the showpiece match.

The winner will face either Barry Hawkins or Mark Allen on Sunday, with those two playing in the other semi on Saturday evening.

Trump was ready to take his break-off shot and get the match underway just before 1.30pm on Saturday afternoon.

But he paused as he inspected the ball before waving it in front of the face of the ref. The ref initially attempted to wipe the cue ball down but then told Trump: “I’ll change it.”

The ref then handed the ball to a colleague, who left the arena and went backstage to find a replacement.

Commentator John Virgo piped up by exclaiming: “Oh, he’s going to change it. You don’t see that very often, new balls please.” And the crowd appeared to see the funny side as laughter erupted around the auditorium.

Trump, who is ranked No. 1 in the world ahead of his semi-final opponent, returned to his seat while he waited for a new ball. He then inspected the replacement, before eventually getting the match underway a few minutes later than scheduled.

Trump and Wilson have already met in two finals this season, with the Northamptonshire-born player winning both of those contests.

The pair have met 32 times in total throughout their illustrious careers, with Trump coming out on top on 18 occasions. But, crucially, Wilson has the upper hand in the bigger matches, having won four of their five clashes in finals.

Trump booked his place in the UK Championship semis after thumping Anda Zhang 6-2 in the quarters on Friday courtesy of an imperious performance at the baize.

And after the clash, the 35-year-old turned his attention to his last-four showdown as he explained: “I think it is great for everyone that there is kind of two players that are achieving some great stuff this season.

“If Kyren wasn’t there, then [my] lead at the top of the rankings would be astronomical. You need someone on your heels to keep pushing you and make you keep going back to practise. We’re both trying to push each other on at the moment.”