This is better from O'Sullivan, picking up the scattered reds and building a break steadily.

He nearly sends the cue ball spiralling into the pocket, to gasps from the crowd! This is snooker on the edge.

Ultimately the break ends at 32, so Zhao still has the chance to win the match tonight.

We wondered if Ronnie O'Sullivan would go hell for leather in this final frame, go down swinging.

But it is Zhao who is playing more attacking snooker, as he sees the finish line ahead.

But a miss of a difficult red into the bottom right means he is not sweeping to victory quite yet.

O'Sullivan leaves a pot on for Zhao, a long red to the bottom left - but the man from China can't find his mark.

But Ronnie also misses his pot. This is so tense, everything is on the line in this frame.

Half a chance for Ronnie? Zhao misses a red to the middle right, and there's a decent spread on the table.

But O'Sullivan chooses the safety. Every shot has to be perfect from here.

Image source, Getty Images

Ken Doherty
1997 world champion on BBC Four

It's a strange situation for Ronnie to be in because he's been so dominant here for so many years. To be on the end of a battering really - and that's what it's been - Zhao has just been sensational.

And there's one frame left tonight.

If Zhao wins it, he is in the final and has beaten Ronnie O'Sullivan with a session to spare.

Well, we were gearing up for Zhao to go one frame from victory - but he hands Ronnie a glimmer with a miss.

O'Sullivan trails by 58, with 59 on the table. Surely not?

No, surely not. He misses the black, and that will be the frame.

Stephen Hendry
Seven-time world champion on BBC Four

If this is how Zhao Xintong is going to play all the time, this is the future of the game we're looking at here. I keep calling him a kid - he's 28 - but he could dominate this sport for the next 10-15 years.

The aggression we saw from Zhao Xintong this morning has returned in abundance here. He's taking on his shots with gusto and moving quickly around the table.

Ronnie O'Sullivan is being beaten at his own game.

Ken Doherty
1997 world champion on BBC Four

Image source, PA Media

I think that's 10 or 11 frames won in one visit by Zhao. That gives you an idea of how well he's scoring. He's just been incredible.

It's hard to play against, no matter who you are.

When your luck is out, it is bang out.

Ronnie O'Sullivan tidily pots a red to the middle right - but the cue ball runs loose, flicks the brown and ends up in the top right pocket.

Groans from the crowd.

So, in answer to Simon's question...

A quick check of the list of finals suggests there hasn't been an all left-handed world final in the Crucible era (unless we've missed something obvious - please let us know!).

There have been three left-handed world champions: Mark Williams (2000, 2003, 2018), Neil Robertson (2010) and Judd Trump (2019).

And, as far as we can tell, none of them beat a fellow leftie in the showpiece match.

But just as I type that, Zhao misses his shot and has to settle for a final break of 85.

No matter, he's two frames away from the world final.

While our dedicated team of boffins delve through the Crucible archives for an answer to Simon's question, we continue to watch one of the finest left-handed performances this arena has seen.

Zhao is flowing here, and has a chance for a break of as much as 144.

One for our stattos...