John Higgins defeated pre-tournament favourite Neil Robertson 13-10 to reach the 10th World Championship semi-final of his career at the Crucible on Wednesday night.
The 43-year-old drew on every inch of his fighting qualities to repel the Australian's bid to fight back from a 9-7 morning deficit.
Twice Robertson moved back to within one frame but Higgins kept his nose in front and finished in style with a 101 clearance in the last.
Higgins will take on David Gilbert, who confirmed his place as an unlikely semi-finalist as he held off last year's semi-finalist Kyren Wilson to claim a surprisingly straight-forward 13-8 success.
Gilbert has suffered his spells in the sport's doldrums, almost dropping off the tour in 2011 and winning only one match in four previous World Championship appearances.
Gilbert admitted: "Who'd have thought I'd end up here? Certainly not me. I have doubted myself a lot over the years.
"I've had a lot of own moments and it's hard to believe in yourself when you're not showing anything.
"I just need to remember to enjoy it because these opportunities don't come around too often."
Judd Trump took a swipe at opponent Stephen Maguire after demolishing the Scot 13-6 to book his place in the last four.
The 29-year-old mocked the Scot's pre-match assertion that he was a "lucky" player by joking: "I got a lot of luck out there - I think that was the only reason I did win."
Trump added: "I think it's obvious that people take it differently. Some people applaud their opponent and some people brush it off like it wasn't their fault - so maybe that's just his way of looking at it."
Trump, who is targeting a place in his first world final since 2011, had built on his stunning opening session by winning the first two frames on Wednesday and establishing a 9-1 lead.
Maguire managed to claw his way back to respectability by taking four of the next five frames including a break of 110 but Trump was in no mood to hang around and swiftly responded with breaks of 68 and 82 to send him over the line with something to spare.
Shrugging off the fact that his win made him the new odds-on favourite for the title, Trump added: "It's always good to beat anybody that comfortably but there is a long battle ahead.
"It was nice to be playing with no real pressure out there and just being able to fully enjoy it with that kind of lead. It was just important to get it over with as soon as possible."
Asked to sum up his own performance in one word, Maguire responded: "S**t" - which will duly earn him a £250 fine from the sport's governing body for swearing in a press conference.
Trump will next face qualifier Gary Wilson whose fairy tale run continued as he converted a 9-7 overnight advantage into a 13-9 win over former two-time finalist Ali Carter.
The Wallsend 33-year-old endured six years off the tour and took jobs as a taxi driver, a barman and a production line worker in a frozen foods factory before grasping his second chance.
Wilson said: "I dropped off the tour and I wasn't good enough to get back on. I was having all these uncertain times when I didn't know if I was going to be a pro again.
"I was desperate to get back on the tour and just scrape a living. So to go from that point to where I am now, in the one-table set-up, is absolutely amazing and the sort of thing you dream of."