Mark Williams polishes off the remaining reds and sets to work on the colours. With blue, pink and black left the Welshman decides to snooker Judd Trump, who nearly goes in off into the middle pocket attempting an ambitious pot.

Gasps from the Crucible crowd.

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Judd Trump notches an impressive break of 71 but misses a red into the middle pocket after sinking a very awkward yellow. Mark Williams sniffs a chance and returns to the table with 67 left on the table and a snooker required.

Should Mark Williams progress to the final to face Zhao Xintong, he will be the oldest player in Crucible history to reach the showpiece event.

Williams is 50, a year older than Ray Reardon when he was beaten in the 1982 final by Alex Higgins.

Image source, PA Media

Shaun Murphy
2005 world champion on BBC Two

A great response from Judd Trump. A world-class frame.

Judd Trump went to speak to the referee after that opening frame. Apparently he had a bit of a grumble about it being cold in the arena.

His cue looks hot in the next frame, though.

A clinical break of 71 from Trump is sufficient for Mark Williams to concede the frame.

Shaun Murphy
2005 world champion on BBC Two

A big reaction from Mark Williams in that opening frame when he stamped his foot after a positional shot. It's the pressure of chasing the dream of a fourth world title with possibly his biggest rival already out. It told me a lot that.

John Parrott
1991 world champion on BBC Two

Judd Trump is going to have change his break because he keeps leaving a red out and can't get the cue ball behind the yellow. The cloth is brand new and it slides on a bid and he cannot get it round there.

Judd Trump unable to make much of an impression when he gets his chance at the table and with two reds left concedes the first frame of the session to Mark Williams.

Shaun Murphy
2005 world champion on BBC Two

I still fancy Judd Trump for the title if I am pushed but you cannot separate these two players. It's hard to pull them part. Two of the best players. I just think as the line gets closer you might have one find an extra gear and run off.

Mark Williams grimaces. He pots the black to move on to a break 57 but leaves the cue ball touching a red and has to hit the ball back up the table to safety. An opportunity, of sorts, for Judd Trump to get himself back in the frame.

John Parrott
1991 world champion on BBC Two

I have been watching the tournament for the whole two weeks and yesterday afternoon's session between Judd Trump and Mark Williams was my favourite session of the entire World Championship so far. It had absolutely eveything.

If I was a young aspiring player wondering how good I have to be to get on the ranking list I would put my cue away, get a re-run of that and watch it from start to finish because it everything. Century breaks, clearances and brilliance from Mark Williams.

Mark Williams with a promising start to the morning session at the Crucible as he move towards a half-century break having partially opened up a cluster of reds with access to the black.

Steve Sutcliffe
BBC Sport at the Crucible Theatre, Sheffield

In Friday afternoon's session in Sheffield, Judd Trump looked set to establish a big lead when he pulled 7-3 ahead of Mark Williams, but the veteran Welshman reined in the 2019 champion to leave the pair at 8-8 overnight.

Three-time winner Mark Williams showed all his snooker nous to catch up with Trump.

Trump, whose glory run six years ago gave him his only Crucible crown to date, extended his overnight lead from 5-3 by taking the opening two frames.

But Welshman Williams, 50, who is aiming to become the oldest ever finalist, rallied to take five of the next six frames on offer.

Just as in their keenly-contested 2022 semi-final, which Trump edged 17-16, the tension was palpable.

It was underlined by Williams uncharacteristically hitting his own cue in frustration when he thought he had given up the opportunity to win the 15th frame, in which he eventually triumphed before rounding off the session with a composed 96.

Right, we'll reflect more on Ronnie O'Sullivan's defeat to Zhao Xintong later.

Time to turn our attentions to Judd Trump v Mark Williams as both players make their way out at the Crucible to boisterous applause from the crowd.

Image source, Getty Images

Zhao Xintong, speaking to BBC Four after reaching the World Championship final:

"I can't believe that. I need to say thank you to Ronnie because he has helped me a lot before. He's my idol.

"I've just tried to enjoy the Crucible. It's my first time playing on the single table here, it's an amazing time for me and I just want to enjoy it because I don't know how many times I can try to enjoy it here.

"I've played here and sometimes the crowd is helpful for Ronnie and he deserves that, he is a legend here so I needed to control myself."

Asked what he will do on his day off on Saturday, he replied: "Have a big lunch!"

Shaun Murphy
2005 world champion on BBC Two

The narrative here is about how well Zhao Xintong has played to this point, including the qualifiers. He has blitzed through this World Championship. He has been irresistible.

Zhao Xintong is the second man from China to reach the Crucible final, and the first in nine years.

Ding Junhui, in 2016, is the only Chinese player to previously reach the world showpiece - he was beaten 18-14 by Mark Selby.

Image source, Getty Images

BBC Two

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Steve Sutcliffe
BBC Sport at the Crucible Theatre, Sheffield

John Higgins and Graeme Dott both whitewashed Ronnie O'Sullivan in sessions on their way to Crucible titles in 1998 and 2006, while John Parrott did the same back in 1994 on only O'Sullivan's second appearance in snooker's blue-riband event.

However, to see it happen on O'Sullivan's 33rd appearance at the event only served to underline his comments - dismissed in some quarters - that he had only reached this last-four stage due to shortcomings of his previous opponents.

His problems from long range were particularly evident against Ali Carter, Pang Junxu and Si Jiahui, but he also toiled when presented with good opportunities to make sizeable contributions of his own.

And the decision to change the ferrule on his cue - the metal part of the cue near the top which affects the amount of side and swerve you can apply to the white - from titanium to the more traditional brass did not reap any rewards.

Instead Zhao Xintong, who O'Sullivan has mentored at times, showcased his full repertoire of shots on his way to a comprehensive victory.

Read the full report...