Mark Williams produced a spirited fightback to only trail Judd Trump 13-11 heading into the last session of their World Championship semi-final.
Trump was threatening to reach his third Crucible final with a session to spare after going 12-5 to the good on Friday.
However, three-time champion Williams dug deep as he won six of the last seven frames to cut the deficit to just two overnight.
Elsewhere, Ronnie O’Sullivan took the last five frames to establish a commanding 10-6 lead over John Higgins.
The effects of Williams’ exertions during his quarter-final victory over Yan Bingtao were evident as he fell 7-1 behind in a torrid opening session against Trump.
But he shared the first six frames of the second with a break of 119 cancelling out back-to-back centuries of 114 and 100 from his opponent.
The Welshman was in first with 52 in frame 15 before missing a red to the corner; enabling Trump to ruthlessly clear with 79. However, he recovered with a timely 70 to keep the distance at six frames.
The Ace opened the evening in style with 120, but Williams responded with a magnificent 137 total clearance – his 14th century of the tournament.
The 24-time ranking event winner followed that up with runs of 58, 53, 57 and 70 – while also stealing the 20th frame on the pink – to cut the deficit to 12-10.
Trump stopped the rot with a timely 113, but Williams controlled the final frame of the session to set up a grandstand finish on Saturday.
Meanwhile, O’Sullivan took command of his record-breaking 13th Crucible semi-final against Higgins.
Locked at 4-4, the Rocket took the first frame of the second session with runs of 45 and 73, but the Wizard hit back by taking the next on the brown before regaining the lead with 53.
But the six-time World champion responded with 99 and 91 to edge his nose back in front, before overturning a 43-0 deficit in frame 14 to move 8-6 ahead.
A run of 70 in the next then guaranteed an overnight lead, which Higgins threatened to reduce in the 16th frame.
However, the four-time Crucible king missed a black when leading by 51 points with 51 remaining.
O’Sullivan subsequently produced a wonderful 43 clearance to force a re-spotted black, which he eventually sank for what could prove to be a crucial steal in the context of this clash.
World Snooker Championship 2022 – Semi-Final Latest Scores
Friday April 29
Judd Trump 13-11 Mark Williams
Ronnie O’Sullivan 10-6 John Higgins