Barry Hawkins fought back from eight frames behind to trail Marco Fu 10-6 and keep alive his hopes of a fourth straight World Championship semi-final.
Fu led 7-1 overnight and continued to outplay Ronnie O’Sullivan’s conqueror as he built a 9-1 lead.
Hawkins, the 2013 runner-up, finally found some form with his first half-century and won three frames in a row.
Hong Kong’s Fu scored a magnificent 136, but Hawkins took the final two frames to edge the session 5-3.
Going into Wednesday’s evening session, which starts at 19:00 BST, world number 14 Fu remains a strong favourite to face Ding Junhui in the semi-finals.
In the other last-eight tie still to be completed, four-time champion John Higgins leads fellow Scot Alan McManus 9-7.
Hawkins hangs on
At 9-1 behind, a Hawkins fightback seemed beyond comprehension, with the Kent left-hander barely able to pot a ball.
But he suddenly found some of the form that saw him beat O’Sullivan 13-12, rather than the play that had plagued his first 10 frames against Fu.
After Fu’s impressive start, Hawkins took a scrappy frame and then scored his first half-century of the match.
Fu stopped a three-frame run with the first ton of the contest, but with his confidence seemingly restored, Hawkins rounded off the session with breaks of 95 and 75.