Shaun Murphy lost 9-8 to Mark Allen in the quarter-finals of the Tour Championship in Milton Keynes despite scoring six century breaks.
Murphy knocked in runs of 110, 117 and 116 in the first session of the match but Allen also produced a ton as the players went in level at 4-4.
Breaks of 100 and 131 helped Murphy move 7-5 ahead and another century saw the world number nine lead 8-7.
Allen fought back to win the last two frames and will now play Mark Selby.
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Murphy's six centuries saw him equal the record for the number of 100+ breaks in a best-of-17 frame match, Stephen Maguire having also reeled off six tons in his victory over Neil Robertson on Saturday to set the new benchmark.
Northern Ireland's Allen had returned to action after the enforced lay-off caused by the coronavirus restrictions when he took part in the Championship League earlier in June but failed to make it out of the group stage.
Murphy, on the other hand, was making his first competitive appearance for almost four months, having sat out the previous event at the same venue.
The 2005 world champion has won the China Championship and the Welsh Open titles during the 2019-20 season.
High quality, high-scoring encounter
The match was a closely fought high-quality affair with the lead changing hands throughout Tuesday's opening session, Murphy making it all square in the eighth with the aid of a fluke.
The Englishman appeared to be taking control but Allen always remained within two frames at least and two breaks of over 70 helped him draw level at 7-7.
Despite Murphy restoring a one-frame advantage Allen battled away to restore parity and then took advantage of his own piece of good fortune - a fluked red - to compile a 62 and progress into the last four.
The world number five, who reached the semi-finals of the tournament last season, will face Selby on Thursday, with Judd Trump playing Stephen Maguire in the first last-four encounter on Wednesday.
Patience and mental strength
Former Masters champion Allen, 34, has now reached the semi-finals of seven tournaments this season, including both ranking and invitation events, and expressed contentment with his performance after securing only his sixth win over good friend Murphy in 19 contests between the pair.
"I was patient all day and stayed strong mentally. I wasn't playing my best snooker but I fought hard," Allen told ITV Sport.
"I felt like I was going to get chances and it was up to me to take them."
The winner of the tournament will collect a first prize of £150,000.