|Betfred World Snooker Championship|
|Venue: Crucible Theatre, Sheffield Dates: 20 April-6 May|
|Coverage: Watch live on BBC One, BBC Two, Red Button, iPlayer, Connected TV, BBC Sport website and BBC Sport app.|
A spirited fightback by Mark Allen proved in vain as he was beaten 10-7 by China's Zhou Yuelong to become the third seed to lose in the first round of this year's World Championship.
The Northern Irishman, the world number six, was below par as he trailed 7-2 overnight and quickly fell 9-2 behind.
Allen, 33, rattled off five frames as Zhou's previously solid form began to crumble with the winning line in sight.
But the world number 35 edged a scrappy frame 17 to progress.
Ali Carter leads Jack Lisowski 5-4, while Barry Hawkins, another Englishman, completed a 10-1 thrashing of China's Li Hang.
The 2013 runner-up dominated the opening session on Wednesday morning, making five half-centuries as he cruised into an 8-1 lead.
Two further scores of over 50 sealed his path into round two when play resumed briefly in the evening.
The world number nine faces the winner of the Kyren Wilson against Scott Donaldson tie, with the former 6-2 up after their opening session.
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Zhou fends off Allen fightback
Zhou, who faces Jack Lisowski or Ali Carter in the last 16, fluffed glorious chances to ensure a place in the last 16 for the first time at 9-5 and 9-6 ahead, as well as missing an opportunity to wrap up the final frame earlier.
The 21-year-old's performance in the last six frames was in stark contrast to the stunning form he showed on Tuesday when hit a ton and five breaks of over 50 to lay the foundations for a seemingly convincing victory.
A break of 70 moved Zhou 8-2 ahead but, despite moving to within a frame of victory, his game fell apart under increasing pressure.
Allen, a double ranking event winner this season, compiled breaks of 68, 60, 131 and 72 as he reduced the deficit to 9-7.
But Zhou somehow regained his composure to halt the charge, puffing out his cheeks in relief as he potted the final pink to ensure his progress.
Allen joins pre-tournament favourite Ronnie O'Sullivan and Belgium's Luca Brecel in losing in the last 32, and exits at the first-round stage for the first time since 2013.
The Belfast-born player, who reached the semi-finals in 2009 and has also made three quarter-final appearances, described his first-session display as "embarrassing".
He said: "I played terribly yesterday and started badly today.
"I was proud with the way I came back and thought I had him on the ropes but I left myself too much to do."
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