Kyren Wilson edged out Anthony McGill in dramatic fashion, winning one of the most remarkable deciders in memory to win 17-16 and reach his first World Championship final.
The eighth seed looked in trouble after losing five of the first seven frames of the final session, McGill's aggression seemingly set to turn the match around, but after a re-rack in frame 32, Wilson produced two nerveless pots to force a decider.
Despite missing a simple red with the match at his mercy, Wilson was able to edge his way into the lead before a fluke on the green effectively sealed victory after both players had failed to take big chances.
It was astonishingly hard on McGill, who had won two previous final-frame shootouts on his way to this career-best run to the last four. But he was made to pay for missing at least two significant opportunities in the final frame, eventually at least, as the Englishman progressed.
The final frame score was 103-83 in Wilson's favour, and no wonder he could only collapse onto the side of the table once the decisive ball had dropped. He has until 1.30pm on Saturday to recover and go again in the most important match of his life.
Wilson had started the day with a two-frame lead and extended it to three, only to be confined to his chair for much of the next hour as McGill produced breaks of 84, 87 and 122 to level the match.
The Scot appeared to be cueing superbly and was desperately unlucky to foul in the next having disturbed the reds, a shot which effectively allowed Wilson to steady the ship and edge back into the lead.
McGill responded brilliantly and after a 98 break saw him move within one of the final, he had his chance. Yet again he was unfortunate, an attempt to disturb two reds just missing its target, spelling the end of his contribution and adding another layer of drama.
Emboldened by an unexpected chance to keep the match alive, Wilson showed all his trademark tenacity and bucketloads of class to pot a thin red and delicate black, his reward the ability to lay a snooker which McGill could only leave over the pocket.
That meant a decider and it was McGill who got in first with a fabulous red, only for another attempt to open the reds up to just go against him. With just a 39-point lead, his decision to take on a tricky red to middle proved a poor one, Wilson potting the same ball to earn his chance.
But the Warrior wobbled with the winning line in site, missing a simple red and allowing McGill back in, the Scot moving into a narrow lead before one final and prolonged safety battle at the end of a four-session epic.
Wilson gained the upper hand with a string of brilliant safety shots, the key one coming as he tucked the cue ball behind the yellow with the sole remaining red hidden from view. McGill just could not escape, his attempts to do so cut short by the fact he had fallen 38 points behind with 35 points left on the table.
Even then there was time for further twists. First, Wilson went in-off, meaning McGill could now win without snookers. Then, both took turns at potting the final red into the middle pocket over which it hung, needing to send the cue ball off the top cushion in order to do so.
Wilson missed twice, McGill once, before the latter made what looked to be a match-winning pot. Then, just as the hard work had been done, he snookered himself on the green and could only leave it on a plate for Wilson - who missed, knowing it was match ball.
The end came in a fittingly dramatic fashion, but one which was unsatisfactory at the end of such an attritional encounter. Wilson sent the green round the angles and, slowly, it trundled towards the pocket, the outcome of the match dependent on whether it completed the journey or came up short.
On its final roll, the green tipped over the edge to leave an exhausted Wilson slumped over the table, and McGill stunned in his chair. Wilson, by the narrowest of margins, had finally done it.
An emotional Wilson said afterwards: "I can't believe it ended like that - I didn't want to send someone home on a fluke."
"I played a great snooker that I thought had won me the match and if it had finished there it would be a different story, but I went in off the red.
"I couldn't believe what was happening. It was absolutely mental. It was one of the best semi-finals you'll ever see but I wish it hadn't ended the way it did.
"You can't just rely on luck to get you a world crown and whoever I play in the final I've got to produce great snooker and I'm not going to get there by fluking balls.
"I can go out and enjoy the occasion and give it my all. I'm going in there to win the world title to but have the pressure on the other guy hopefully plays in my favour."
McGill, who had already battled through two final frame deciders in the tournament, paid rich tribute to Wilson but added: "I feel like I've had something stolen from me - not by Kyren, but by the snooker gods."
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