Mark Selby set a Crucible record of six centuries in a match as he established a 12-4 lead over Stephen Hendry, which leaves him needing one of the afternoon's nine frames on Monday to take a place in the quarter-finals of the world championship.
The twice Masters champion made breaks of 125, 108, 98 and 129 to take a 7-1 lead after one session and 100, 127, 87 and 117 in the second. Hendry's 114 gave him his only success of the opening session and consecutive frame winners in the second at least helped him to avoid the indignity of defeat with a session to spare. The loss of the last frame of the day after Selby needed four snookers completed a dreadful weekend for the Scot.
Selby, now the 7-2 favourite for the title, has equalled Hendry's 1994-95 record of 53 centuries in a season although there were never sufficient tournaments in the 42-year-old Scot's prime to play more than 100 matches, as Selby has in this campaign.
Ronnie O'Sullivan, far from his best but displaying patience, a renewed appetite for competition and more readiness than usual to accept his shortcomings, had his first-session 6-2 lead over Shaun Murphy cut to 9-7 at the close.
Murphy had injected some pre-match needle into the game by describing as "pathetic" O'Sullivan's initial reluctance to pot the final black for a maximum at September's World Open on the grounds a 147 did not carry a bonus. He also criticised him for not sharing the load of promoting the game through minor events. O'Sullivan declined to respond other than to say: "Shaun wants to play the ambassador role and that's great but I've never wanted to do that." The three-time world champion said he had "done more for snooker than any other player in the last 10 years in terms of putting bums on seats".
Murphy's failing was missing crucial pots. Set to reduce his arrears to 6-5, he erred unexpectedly on 44 to let O'Sullivan in for 76 and 7-4. Trailing 8-5, he missed an easy red with the balls wide open to allow O'Sullivan in for 95 and 9-5. Even so, by taking the last two frames of the day without O'Sullivan scoring Murphy can still hope to prevail on Monday.
The quarter-finals start on Tuesday with Mark Williams taking on Mark Allen, who was so clinically depressed in the weeks before the championship that he scarcely picked up his cue. Two 13-12 wins over Matthew Stevens and Barry Hawkins have raised the 25‑year-old Northern Ireland No1's spirits although, when he broke off against Stevens at three down with four to play, he changed his intention to scatter the reds at random only on his last backswing. He fell 7-3 adrift of Hawkins although he got into a seven‑frame winning steak to lead 10-7.
"I felt I needed to quicken up Barry's not negative but he's steady. He can keep you in your chair for a long time," said Allen. "I needed to play at my own rhythm. I hit the ball much better then."
A 12-9 win for Allen looked imminent but metronomically efficient breaks of 80, 117 and 92 brought Hawkins level before he bungled his break-off in the decider. "I seem to be able to find something when the pressure's on," said Allen. In this case, Allen not only made a match‑winning 96 but was on course for a 147 maximum until a "kick" on his thirteenth black left him out of position. "When I was coming back against Matthew, he gave me a lot of chances. Against Barry I hadn't had a chance for three frames."
Graeme Dott showed his will to win in beating Ali Carter 13-11 and will provide a stern quarter-final test for the 21‑year-old Judd Trump, already a Crucible crowd favourite judging by the receptions his entrances are receiving.