Ronnie O'Sullivan was in inspired form as he reached the 888.com World Championship semi-final after a 13-7 win over Chinese rookie Liang Wenbo.
The two-time champion was locked at 4-4 overnight with left-hander Liang after the opening session.
Liang, who practices at the World Snooker Academy at the English Institute of Sport in Sheffield, opened up a 2-0 lead over favourite O'Sullivan.
He began with a break of 80 and then compiled 101 points in frame two with O'Sullivan - who hit a 147 against Mark Williams - failing to trouble the scorers.
However, the two-time champion responded with a break of 113 to halve the deficit, and then levelled in frame four, in the best-of-25 last-eight tie.
Liang, aged 21, won two of the next three with 100-plus breaks to edge 4-3 ahead but O'Sullivan restored parity at the end of the session with a break of 64.
O'Sullivan though was quick out of the blocks on Wednesday morning, taking the opening six frames to take a 10-4 lead, peaking with a 138 break.
The double World Champion played well, but was offered plenty of openings by Liang's sometimes reckless potting style, something which he will have to tame if he hopes to reach the elite top 16.
At least Liang finally got his name on the scoreboard in the penultimate frame of the morning session, ending O'Sullivan's six-frame winning streak, to make it 10-5.
But the Rocket clinched the final frame to go 11-5 ahead, after a foul on the black as Liang attempted another ambitious long red, meaning O'Sullivan needs just two frames from Wednesday evening's session to reach the semi-finals where he will meet Stephen Hendry.
Liang opened the evening segment by taking the first frame after a 66 break, little pressure on the rookie in last chance saloon. And he was in the points again in the 18th frame, racking up another half century, but gifted O'Sullivan a route back only for a missed brown to leave the frame poised at 58-53.
Faced with a long shot, most players would have opted for safety, but Liang dropped the brown, but then incredibly missed an easier blue and O'Sullivan wasn't going to spurn another gilt-edged chance. Facing a 12-6 deficit, defeat looked inevitable for Liang, as he sat shaking his head in his seat.
A 54 break must have left the Rocket thinking he had one foot in the semi-final, but with Liang's willingness to shoot from all angles he clawed his way back to snatch another frame at 12-7. But the end was close.
A missed black to the corner thwarted Liang on 41 and O'Sullivan was ruthless in his finishing as he cleared for a 13-7 victory.
Hendry started the afternoon session at 11-5, Day took two of the opening three frames to claw back to 12-7. But the Scot finally shook off the stubborn Day to clinch victory 13-7 and his 12th Crucible semi-final.
Joe Perry edged out Stephen Maguire 13-12 after a marathon session and will now face Ali Carter - who emulated O'Sullivan's feat of 24 hours earlier by knocking in a maximum 147 break - who beat Peter Ebdon 13-9.
Both of the semi-finals start on Thursday.