Ronnie O'Sullivan insists he can avoid a Crucible meltdown as he closes in on a fifth World Championship title.
O'Sullivan credits sports psychiatrist Dr Steve Peters as the key figure behind his well-being on and off the table, with the once-volatile former world No 1 now capable of keeping his feelings in check.
Where once O'Sullivan could lose focus in a flash, working with Peters has prepared him for the long-haul demands of snooker's stiffest test.
He has overcome Marcus Campbell and Ali Carter and looked to have one foot in the semi-finals after racing to a 7-1 lead in his last-eight match against Stuart Bingham.
O'Sullivan made breaks of 79, 54, 111, 60, 87, 133 and 78 in one of his finest performances at the Crucible.
Barring a dramatic collapse, he will secure his place in the final four, possibly with a session to spare.
Not since Stephen Hendry won five-in-a-row from 1992 to 1996 has a world champion successfully defended the title. Although O'Sullivan has complained of feeling "jaded" at his comeback tournament, after almost a year out, that is a physical issue. Mentally he is pinpoint sharp.
"I'm managing my emotions a lot better now," O'Sullivan said. "In the past there'd have been a moment in my matches against Marcus and Ali when I'd have probably thought, 'I want to be out of here, I want to go home', and I'd have not deliberately lost but subconsciously I would have given up.
"That won't happen again, none of those meltdowns will happen, no matter how frustrated I may be with myself out there. I'm able to put that on hold until the game's finished."
Should O'Sullivan reach the semi-final, his opponent is almost certain to have come through a difficult game with Judd Trump and Shaun Murphy locked in a titanic tussle at 8-8 when their last eight game resumes this afternoon.
Murphy looked to be surging into the semi-finals when he extended his 6-2 lead from the first session to 8-3. At that point, had the former world champion won the final five frames, he could have qualified with a session to spare.
Instead, Trump came roaring back and Murphy managed to score just one point in the next three frames which included a 118 break as Trump closed the gap to two frames. The left-hander then clinched the final two frames of the session, however, he will need to maintain his momentum this afternoon.
On the other side of the draw, Ricky Walden leads Michael White 6-2 after an impressive display as he looks to secure a spot in his first World Championship semi-final, while Barry Hawkins is on course for another surprise as he leads Ding Junhui 9-7.
Hawkins saw off world No 1 Mark Selby in the previous round and led 8-4 at one stage yesterday before Ding battled back to keep himself in contention.
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