Ronnie O'Sullivan set up a showdown with Judd Trump after producing a rousing comeback to defeat Kyren Wilson 5-3 in the World Grand Prix quarter-finals.
Trump also reached the semi-finals on Thursday, putting in a fine performance to beat Martin Gould 5-2, notching a 142 break in the process, the highest of the tournament.
A slack start from O'Sullivan gave Wilson the chance to get into his work quickly, and though he fell short of a century, a break of 97 was more than enough to win him the opening frame.
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Errors continued to plague the Rocket and he soon found himself 2-0 down, with Wilson edging the second frame 65-43.
Some fluency returned to the world champion's game with a 66 helping him take the third frame convincingly, but once again mistakes halted him in the fourth.
After potting a colour when trying to blast his way out of a snooker, Wilson returned and his second 50-plus break of the night put him in a commanding 3-1 lead at the interval.
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O'Sullivan returned from the interval looking sharper and his highest break of the match yet, 84, cut the deficit to one.
Wilson was on the verge of restoring his advantage but a poor effort on the pink, which sent the cueball falling into the corner pocket, allowed Ronnie O'Sullivan to mop up the final two colours and draw level.
O'Sullivan's fine comeback continued as he rattled off 86 to move ahead. With Wilson needing to win the ninth to force a decider, the Rocket snookered him a number of times before doing enough to get over the line.
In the day's other action, Mark Selby beat Anthony McGill 4-2, Jack Lisowski bested Robert Milkins 4-0, Zhao Xintong ousted John Higgins 4-3, and Hossein Vafaei surprised Ding Junhui 4-1.
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Northern Ireland Open
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