Ronnie O'Sullivan is a five-time world champion. AFP/File/DALE DE LA REY
O’Sullivan was close to missing out on a first world final appearance since 2014 when he trailed 16-14 in Friday’s semi-final in Sheffield.
But the former world number one refused to surrender, reeling off the last three frames to earn a seventh appearance in the title match.
O’Sullivan and Wilson will meet on Saturday and Sunday in the best of 35 frames final.
A limited number of fans will be allowed into the final after the British government announced that its programme of pilot events to test the return of spectators at sporting events can resume from this weekend.
O’Sullivan’s tense victory capped a remarkable day at the Crucible Theatre.
The 44-year-old, who won his last world title in 2013, looked to have lost focus when he lashed wildly at a pink and enabled Selby to sweep one frame from victory.
But O’Sullivan responded by blasting a 138 clearance followed by an equally quickfire 71 to set up a final frame.
After an extensive period of safety play, it was Selby who wobbled, catching the middle jaw with a red and allowing his rival to sweep up and seal an improbable victory.
– Tears of joy –
Earlier, Wilson wept tears of joy as he reached his first World Championship final after surviving a thrilling last frame to beat Anthony McGill 17-16.
Scottish qualifier McGill had been one frame from victory, but world number eight Wilson hit back to win the last two.
A chaotic finish saw McGill miss a snooker eight times in a row before Wilson fluked a green to effectively seal the victory.
England’s Wilson struggled to contain his emotions after his decisive shot and broke down during a post-match television interview.
“I can’t believe it ended like that. I didn’t want to send someone home on a fluke,” said Wilson, who beat defending champion Judd Trump in the quarter-finals.
“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.”
McGill added: “I feel like I’ve had something stolen from me, not by Kyren, but by the snooker gods.”
Wilson had returned for their concluding session with a 13-11 advantage and stretched his lead to three frames with a nerveless break of 94.
But McGill stormed back with consecutive breaks of 84, 87 and 122 to achieve parity at the mid-session interval.
In the deciding frame, both players missed chances, with McGill running aground on 39 then Wilson missing a simple red to middle on 47.
With the black teetering over the top pocket, Wilson snookered McGill on a nearby red and the Scot missed it eight times in a row – leaving him requiring snookers.
After an extended safety battle, Wilson fluked the green via three cushions to seal a memorable triumph.
Seven-time world champion Stephen Hendry said on the BBC: “This is the most bizarre end to a World Championship match I’ve seen.”
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