Si Jiahui continued his dream debut run to edge out Anthony McGill in a deciding frame for a place in the World Championship Semi-Finals, as Mark Selby swept aside John Higgins.
Si, who won three qualifying matches to reach The Crucible, held his nerve in a tense, late-night decider to deny McGill and reach the one-table setup.
The 20-year-old sensation becomes the youngest World Championship semi-finalist since Ronnie O’Sullivan in 1996 and the first debutant to reach the Semi-Finals since Andy Hicks in 1995.
The two players headed in to the final session locked level at eight apiece and played out a nail-biting climax featuring a host of unforced errors.
It was McGill who started the evening by securing successive frames, and remained two clear at 11-9, before Si returned from the interval to claim the next two frames and restore parity.
The world number 80 then produced a stunning break of 87 to hit the front, but only for McGill to hit back with a majestic clearance of 130 to force a decider.
Chances fell to both players to land the decisive blow, but it was the youngster who held his nerve to get over the line and set up a show-down with Luca Brecel on Thursday.
“I feel very lucky because there were times I didn’t think I could win,” Si told BBC Sport.
“I kept it tight and kept my nerves under control. I just wanted to concentrate to perform under this extreme pressure. My mindset changed but I held myself together very well.”
A raw McGill admitted: “I didn’t deserve to win.”
“The standard that I played the whole game was atrocious, it was so bad. I was embarrassed actually because I was thinking everybody in there had paid their money to watch. I just missed so many easy balls.
“Credit to Si, 20 years old, incredible. I thought he played the decider perfectly, he looked super cool.”
Earlier in the evening, Selby stormed to a 13-7 victory over fellow four-time World Champion Higgins to reach his eighth Crucible Semi-Final.
Higgins had opened up an early 4-1 lead on Tuesday before Selby reeled off three frames in a row to level the contest overnight.
A gruelling second session saw the pair play out just six frames as Selby dominated to open up a 9-5 lead, making a break of 100 in frame 14 for his 100th century at The Crucible.
Selby added to his advantage with a break of 64 to open up the final session, before Higgins replied with a 65 to trail 10-6.
Back-to-back breaks of 67 and 91 saw ‘The Jester’ move to the verge of victory, and though Higgins rallied with a superb break of 102, Selby sealed victory with a 67 in the following frame to remain on course for a fifth world title in the space of a decade.
“I thought I played faultless really from the start,” Selby told BBC Sport.
“To get the first frame on the board was key. You can’t give someone of John’s class a four-frame lead. Then at 4-1 I had an outrageous fluke in the middle and if it goes 5-1 it is a completely different game.
“When I feel like I have had to do it [answer questions], I have done it which has been pleasing because that has been missing for a little while and only gives me confidence.”
Selby will now face reigning UK Champion Mark Allen over four sessions for a place in the final.
“I played a terrible first frame today when it should have definitely gone 5-4 in front and from then on it was all downhill for me and Mark got stronger and he totally took me apart,” admitted Higgins.
“His safety was incredible and I was in bad positions all day. He is an incredible animal on a snooker table, he just doesn’t let you breathe. He is a master at the game of snooker.”
World Snooker Championship 2023 Day 12 Results
Wednesday April 26
Mark Allen 13-10 Jak Jones
Luca Brecel 13-10 Ronnie O’Sullivan
Mark Selby 13-7 John Higgins
Si Jiahui 13-12 Anthony McGill
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