Another long red, the potting under pressure is amazing. The cue is close to the side cushion, but Higgins pots the pink ball too, 48-25 to him, five reds on the table.

Williams hits the black with a full-table shot and that seven-point foul nudges Higgins' lead to 41-25.

Remember, these two have a history that goes way back, with John Higgins just edging the head-to-head, 22-20, on matches won

Graduates of the so-called 'Class of 92' along with Ronnie O'Sullivan.

Higgins (four) and Williams (three) have seven world titles between them and a combined age of 99.

And here they are slugging it out in a decider, trying to get to the last four again.

The yellow goes into its pocket, but Higgins can't separate two reds that are close to the right middle and safe he goes, 34-25 Higgins.

What a long pot from Higgins. He's on the yellow, but the cueing is hampered by the brown, 32-25.

There are seven reds on the table, three close to cushions. A couple of superb safety shots from both men. Who will crack first? 31-25 to Higgins.

Williams misses a long red, but looks to have got lucky with nothing on for the Scot. Certainly nothing easy, 31-25 to Higgins.

Higgins gets to a six-point lead, 31-25 then has to go safe with the cue ball nestled on the baulk cushion. Still life in this one.

One wrong shot from Higgins and Williams will have a great table. At the moment the Welshman can just sit, watch, wait and hope. Higgins' frame to lose from here, 17-25 in Williams' favour.

Image source, PA Media

Jon Hayes: What would the odds have been at 12-8 to Willo?!?! No one would have put a bet on surely! Madness to even think about it…Mark Williams was gone for all money… Victor wins it now!

Higgins is up and running with a red and a black. Lots of work still to do, he's 8-25 down.

The black stays out from Williams and now Higgins has an easy starter, 25-0 behind.

Another great long red from Williams, who has left himself a horribly difficult black ball. 25-0 to Williams.

But Williams doesn't like the look of the table and plays safe, sending the cue ball down near the baulk cushion. 24-0 to Williams.

Ryan Glendenning: The Williams vs Higgins match really is living up to expectations and more. A final frame decider 12-12 after a great comeback from Higgins. Backing Williams to cross the line now.

Three reds, three blacks from Williams.

Williams pots the first ball of the decider, a superb long red and is on the black. The first chance, albeit with a lot of work to do, is his.

Steve Sutcliffe
BBC Sport at the Crucible Theatre, Sheffield

John Higgins has won nine of the 10 deciders he has played at the Crucible Theatre.

A massive ovation from the fans and a shake of the hands between the competitors as the 25th and final frame gets under way.

Here we go, 12-12. Who will win this frame and get into the semi-finals?

John Virgo
1979 UK Championship winner on BBC iPlayer

This will be one of the biggest frames of their long careers.