Graeme Dott survived an almighty scare to book his place in the semi-finals with a dramatic 13-12 win over Neil Robertson at The Crucible.
Dott almost paid the price for a careless missed red in the 22nd
Resuming 10-6 ahead, Scotland's Dott looked to be cruising into the last four as he established a 12-8 lead.
But Australia's Robertson hit a rich vein of form, winning four frames in a row - including breaks of 74 and 103 - to force a final-frame shoot-out.
Both players had chances to seal the match, but Dott held on for the win.
"I thought the whole match had gone perfectly for me," said Dott, runner-up in 2004.
"I played well in the first session and the second half of the second but then Neil played fantastically well today.
"Being in the semi-finals, I've got a good chance because I know I'm playing well."
Meanwhile, Robertson claimed he was "by far the better player throughout the whole match".
"My positional play is so much better and I really believe I'm one of the best players in the world now," said the 24-year-old.
"Obviously I have to start winning tournaments to prove that, but I don't think anyone can out-play me, long-potting wise."
Robertson started the session with a 53 break to take the opener, and followed it up with a 106 in the 18th frame.
But the 17th and 19th frames went to Dott to give him a comfortable 12-8 lead at the interval, and Dott looked certain to stroll into the semi-finals.
Robertson had other ideas though, and tested Dott's nerves to the limits as he made a 74 break to cut the gap to three frames.
Dott should have sealed the match in the next frame, but missed a straightforward red as he paid too much attention to the positional shot.
Building up momentum, Robertson made a 103 in the 23rd frame - after Dott had been forced to play into the reds when the referee replaced the white in the wrong place - and then took the next to force a deciding frame.
In the decider, the 28-year-old Glaswegian went 50 points ahead with a 35 break, but broke down to let his opponent back in.
The pivotal moment came on the yellow. After Dott had fouled by missing the ball, Robertson chose not to put him in again and instead played a poor safety shot that left the yellow on.
Dott cleared to the frame-ball brown, and it was all over when Robertson, trying to lay a snooker on the pink, only succeeded in potting the ball.
G Dott (Sco) 13-12 N Robertson (Aus)
53-78 58-53 77-4 (61) 76-45 73-15 (73) 8-73 4-132 (109) 69-39 87-4 (66) 64-48 90-32 12-70 82-5 58-72 (71) 68-62 (Dott 61) 7-64 (62) 0-68 (53) 60-10 0-106 (106) 72-33 1-74 (74) 56-67 0-111 (103) 14-63 60-48