Mark Allen left with little choice but to pot the blue.

He works about attempting to find a snooker with just black and pink remaining...then produces the most incredible shot.

The pink is close to the top-right pocket at the baulk end and Allen manages to guide it off four cushions and in behind the black at the opposite end of the table.

This is now officially the longest frame in the history of the World Snooker Championship. Over 90 minutes and counting.

Mark Allen requires just one snooker now.

The difference is 21 points between the players with 18 left on the table.

John Parrott
1991 world champion on BBC Two

Oh my goodness, what is going on?

Can you believe that - anything else in this frame?

Wu Yize take a bow.

He pots the brown into the left middle pocket with a double off the cushion near the corner pocket on the opposite side of the table.

However, he shoots himself in the foot with attempted pot on the blue by which sees it come back down the table and knock in the black.

Chaos at the Crucible.

Brown, blue, pink and black left.

Wu Yize has 78 points and Mark Allen has 54.

Wu rolls the brown over the pocket before a bit of hit and hope from Allen to dislodge it.

The black ends up hanging over the same pocket it was lingering during the stalemate to the amusement of the crowd.

Hazel Irvine
Snooker presenter on BBC Two

This is the most tortuous frame of snooker. We've been imprisoned by it.

A brilliant long red from Wu Yize gives him a mini break as he follows up with the pink, red and then black.

Mark Allen needs snookers with just the colours as he returns to the table.

"You thought it was over!" he quips to the crowd before attempting to hide the cue ball.

Stephen Hendry
Seven-time world champion on BBC Two

It's been a horrendous frame but it's helped Wu Yize so much.

He didn't look like winning another frame, but the ludicrous nature of this frame has just helped to lighten the load on him and free him up, forget what was happening to him in this session.

Another safety exchange ensues between Wu Yize and Mark Allen.

This frame is now into one hour and 15 minutes.

The Crucible crowd have done well to settle back down into the rhythm of the contest.

John Parrott
1991 world champion on BBC Two

Mark Allen might be steaming inside but he has a frame to win here.

A break of 41 from Wu Yize before he resorts to a safety shot.

He leads the frame 61-47 with two reds left on the table.

Yes he can.

Wu Yize bridges near the pocket and cuts it in a red.

With the black back on its spot. He sets off building a break.

Finally the impasse is broken. Well, broken-ish.

With the white close to the reds clustered around the black Mark Allen fouls by knocking in the black.

Can Wu Yize find a pot now?

Mark Allen asks referee Marcel Eckardt whether he would be more lenient if he were to go for a pot.

"If it's still a stalemate after you go for the pot, that might still be the case," Eckardt says in response.

"Just going for the pot doesn't mean you will have opened up the stalemate."

Stephen Hendry
Seven-time world champion on BBC Two

Even if the black does go in, are there any reds potable?

This is the dark side of snooker.

Image source, PA Media

There's slow hand clapping from the Crucible crowd which gets referee Marcel Eckardt's back up again.

A slightly terse exchange over how to progress this given the stalemate follows between Mark Allen and Eckardt.

John Parrott
1991 world champion on BBC Two

Mark Allen says he doesn't want a re-rack, but the referee is in charge and the referee should be in charge.

I can understand from Mark's point of view, but the referee has the authority there to do something about this.