Match Notes:

Ronnie nails Williams in a snooker, gets five fouls and the chance to knock in the match winning century break. Fabulous stuff today by Ronnie.

O'Sullivan regains his two frame lead with a ton and now is just one frame from the quarter finals. What has Mark got left in the tank?

Mark has blasted through frame 21 with a century and closed to 11-10 behind. Could we be heading for yet another heart-stopping decider. The new European under 19 champion Jak Jones is here today to cheer on Mark.

Williams misses a long range red and Ronnie pounces with 75 to open a two frame lead.

This match is just so good. This time it's Ronnie who rifles in a century break to regain the lead.

I did say don't blink. The superb quality continues at Williams levels with 53 before losing position.

O'Sullivan pops in 53 to take the first of the day but Williams was unlucky to go in off the black when he had the first chance.

Here we go then, don't blink, it's the run to the line.

Another rivetting session ends with O'Sullivan firing in a 72 break to level the match again.

O'Sullivan closes again. One more frame tonight.

Williams reopens the two frame buffer. Ronnie had one chance but missed black off its spot.

Ronnie closes the gap, despite a vain attempt by Williams to get snookers, after Ronnie forced three fouls from Mark.

Great stuff from Williams and he's two clear at the interval.

A nerveless cross double on the black by Williams gives him the 11th frame and the lead for the first time.

And Mark fizzes through the second frame with a couple of visits.

 Ronnie fizzes through the first frame of the night in just over five minutes.

 Williams rattles in three frames on the spin to level the scores after a higly entertaining first session.

 Back to back frames for Williams and the high quality scoring continues.

 A rare safety error by O'Sullivan and Williams steps into to close the score to 4-2.

Ronnie is in imperious form this afternoon. He's already rattled in 67, 78, 83 and 78 again.

O'Sullivan blazes into a 3-1 lead at the interval.

 Good afternoon. It's  fine, sunny, and packed Sheffield. they're queuing round the block to get into this match. Other spectators are out taking the sun and reccovering from the dramatic match between John Higgins and Steve Davis.