Wu Yize 6-2 Mark Allen after first session, match continues at 14:30 BST on Friday
Play briefly halted after third frame because of power outage
John Higgins 4-4 Shaun Murphy, play resumes at 10:00
Semi-finals are best of 33 frames - first to 17 - and conclude on Saturday
Wu 2-2 Allen
On a break of 28, Mark Allen misses a red with the rest.
He's still 33 points behind with 51 remaining.
Wu Yize pushes the boat out going for a plant that didn't look like it was ever on and suddenly Allen is back at the table with another chance.
Wu 2-2 Allen
Ken Doherty
1997 world champion on BBC Two
It's very early days and there are going to be lots of twists and turns, but this could be one of them.
Wu 2-2 Allen
Ohhh, the eighth black does not drop and Wu Yize looks a bit disconsolate going back to his seat.
Not only is it a good chance for a 147 missed, he might not even win the frame.
Wu 2-2 Allen
Ken Doherty
1997 world champion on BBC Two
The way the reds are positioned as well, no more cannons required here. Just keep a nice close rein on the cue ball and we could be in for something very special.
Wu 2-2 Allen
Six reds, six blacks for Wu Yize...
Wu 2-2 Allen
Not the best of starts after the interval for Mark Allen, who goes in-off when playing a safety shot.
He clearly wasn't happy with something immediately after he struck the cue ball and referee Marcel Eckardt asked the crowd to make sure phones were turned off.
Wu Yize has the first chance to score in frame five.
Wu 2-2 Allen
The players are back out at the Crucible Theatre for the next instalment of this semi-final.
Mark Allen and Wu Yize will play another four frames before the close of play this evening.
They both made two breaks above 50 in the opening four frames.
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Never seen Mark Allen play so well. Wu Yize's early lightning start seems to have galvanised him...
Tom, Walsingham
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Higgins is a master of match play, and a master at grinding out a tough session, and with the pressure at this stage at the Crucible, the longer and harder the match, the harder he is to beat. I think this might be his year!
Dominic, London
If you weren't with us earlier, a reminder that the first session between John Higgins and Shaun Murphy ended level at 4-4.
They will resume at 10:00 BST on Friday.
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As cute as the lambs were on BBC Two during the outage, I prefer the snooker!
Chris, Sheffield
All being well, that'll be the final disruption to the TV coverage of the evening...
Wu 2-2 Allen
Steve Davis
Six-time world champion on BBC Two
When the screens went blank at home, it was obvious in the room here that something had happened.
Lights went off and cameras stopped filming the players.
Mark Allen was aware that something weird had happened, and how good a performance to actually keep his standard up without getting confused by what was going on.
That's somebody who's on point at the moment.
Wu 2-2 Allen
All square at the interval.
Mark Allen bounces back well from losing the first two frames and it's 2-2.
Wu 2-1 Allen
Ken Doherty
1997 world champion on BBC Two
It's been a really entertaining four frames.
Wu 2-1 Allen
A simple black from Mark Allen means Wu Yize requires a snooker, and a thin cut on a red into the left corner means the Chinese player won't be coming back to the table.
Wu 2-1 Allen
Steven Hallworth
Snooker commentator on BBC Two
More than anything, this is sending a clear message to Wu Yize that he won't have it all his own way, that Mark Allen is up to the challenge and up for the task.
Wu 2-1 Allen
BBC Two
Hurrah! We have live TV pictures once again!
Mark Allen has a 39-1 lead in frame four.
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Wu Yize shouldn't be written off by the media so much as being "a future world champion in the making". He's already world class and has a real chance to win here.
Keegan, Jersey
Wu 2-1 Allen
Steve Sutcliffe
BBC Sport at the Crucible Theatre
There don't appear to be any issues with the lights, wifi and hopefully the press room kettle, as things stand.
And pictures have just returned to our screens, so presumably play is about to get back under way.
Well, then.
This is new.