Qualifier Gary Wilson reached his first World Championship semi-final by beating two-time finalist Ali Carter 13-9 at The Crucible.
Carter surged into a 3-0 lead but Wilson hit back by taking five in a row and maintained his two-frame advantage at 9-7 after the second session.
The next four frames were shared, but Wilson coolly took the two he needed to secure victory.
Masters champion Judd Trump resumes 7-1 up against Stephen Maguire.
That means the Englishman could win with a session to spare over the Scot.
David Gilbert is 10-6 ahead against Kyren Wilson, while former champions John Higgins and Neil Robertson resumed on Wednesday morning tied at 4-4.
Former taxi driver among snooker’s elite
Gary Wilson’s progression to the latter stages of snooker’s biggest tournament is a remarkable story. The Tynesider, 33, has never won a ranking title and is into the semi-finals in Sheffield for the first time.
The world number 32 has had a tough run to the last four, having to win three qualifying matches to reach the televised stages and beating three-time champion Mark Selby in the second round.
He quit his job as a taxi driver after turning professional again in 2013, having tried for seven years to regain his tour card.
He said: “There are certain times in that period where I did not even think I would be a professional again.
“It was ridiculous, I was at such a low point. I was desperate to get back on the tour and make snooker my career. From that point to now is amazing; I am proud of myself.
“I remember being off the tour and struggling for money, thinking: What job do I get next? I had been playing snooker since the age of eight, I put my heart and soul into it every day, missed school and nights out with my mates – where was my life going? I am so happy to be making a living out of it now.”
Beaten opponent Carter added: “Gary has to be the favourite to win it now, the way he has been playing. It was the performance of his life, an amazing performance. You have to take your hat off to him. I did not think he could play that good.”