Four-time world champion Higgins began strongly in Manchester on Monday, but blew a 4-1 lead in losing nine of the last 12 frames to crash out of the elite 12-man event amid a strong sense of regret.
Despite producing fine breaks of 85, 75, 55, 66, 82, 62 and 86, the 31-time ranking event winner lost three frames on black balls and also watched Allen roll in a pivotal break of 93 leading 8-7 in the 16th frame after Higgins touched a green with his sleeve when lining up a long red from the D.
The Scotsman turned professional in 1992 and has lifted the world title in 1998, 2007, 2009 and 2011, but admits his 30th trip to the Crucible for the World Championship later this month (April 20-May 6) could be his “final go” at winning the sport’s biggest event for a fifth time.
Speaking after his defeat to Allen, a clearly deflated Higgins said: “I should have been in front today, lost a bad frame when I definitely should have made it 5-2 I think.
“Then it is 4-4, but I think Mark played better tonight. Again, I missed two or three unforgivable balls at this level that you cannot afford to miss.
“My long game was non-existent as well. At this level, it’s not good enough. It’s not good enough against the best players.
“I just need to dust myself down a couple of weeks before the worlds, try to get some good practice in and go there and give it a final go maybe.”
Higgins last won a major ranking title with a 10-3 victory over Ronnie O’Sullivan in the final of the 2021 Players Championship.
The celebrated ‘Class of ’92’ icon is likely to be seeded 13th at the Crucible unless Tom Ford or Barry Hawkins can reach the final of the Tour Championship on Sunday.
Allen progresses to a quarter-final meeting with Ding Junhui on Wednesday after compiling three centuries against Higgins, but had words of encouragement for the Wishaw player.
“I think he’s actually being a bit too hard on himself,” said Allen on ITV. “He’s not playing bad snooker. Like I said, it is fine, fine margins.
“Three black balls and a real uncharacteristic foul by John. It’s almost like he has to win one of these close games.
“I don’t feel like we have to talk John up. He’s a four-time world champ.”