Mark Selby fired a break of 124 in the final-frame decider against Thai qualifier Noppon Saengkham to book his place in the last eight at the World Snooker Championship.
Resuming at 8-8, Saengkham had got the better of some gruelling opening exchanges and won a 48-minute frame to edge into a 10-9 lead.
But a cool 77 break hauled Selby level again and he pounced on a missed red to the middle in the next by Saengkham to move back in front.
A brilliant clearance of 92 from the Leicester man moved him within one frame of victory at 12-10. Saengkham responded superbly, reducing the deficit in two visits, then levelling with a break of 90.
The Thai player, 28, got the first chance in the decider but ran out of position and Selby seized his first opportunity to win the match in style.
World No 89 Jamie Clarke continued his dream form at the Crucible by establishing a 6-2 overnight lead over fellow qualifier Anthony McGill.
And Mark Williams revealed how a blunt appraisal of his performance from his 13-year-old son Kian spurred him on to beat Stuart Bingham.
The three-time former winner turned an 8-8 overnight tie into an impressive 13-11 win over his fellow former champion, taking him into the last eight at the Crucible for the ninth time where he awaits either Ronnie O'Sullivan or Ding Junhui.
Williams said: "I walked in and the first thing he said was, 'Why are you so crap?' I'm going to take him on the golf course this afternoon and give him an absolute b******ing because of all the stick he's been giving me these last few days."
The 45-year-old Williams emphasised his newly relaxed demeanour, laughing at himself for missing a simple black in frame 11 and tweeting about the "best of 5" showdown as the pair sat locked at 10-10 at the mid-session interval. They shared the next two before Williams pulled away for victory.