Tyson Fury's undisputed heavyweight title fight against Oleksandr Usyk has been postponed after the Briton sustained a "freak" cut in training.
Fury, 35, was cut in sparring at his training camp in Saudi Arabia on Friday in preparation for the bout on 17 February in Riyadh.
The injury above Fury's right eye needed "urgent medical attention" and "significant stitching".
In a statement, the Briton said he was "absolutely devastated".
Fury is the WBC champion with Ukraine's Usyk, 37, holding the WBA, WBO and IBF belts.
If the fight does take place at a later date, the winner will be crowned the first undisputed heavyweight champion in the four-belt era.
Fury said he had been preparing to face Usyk "for so long" and was in "superb condition".
"I feel bad for everyone involved in this huge event and I will work diligently towards the rescheduled date once the eye is healed," he added.
In a later Instagram post he wrote: "Can't help getting injured in sparring but what I can say was Usyk was in trouble. I am in fantastic shape. I will reschedule soon as I can. 2024 a massive year for team GK."
Usyk's promoter, Alex Krassyuk, commented underneath: "Wishing you soonest recovery. God sent you a sign. Think of retirement, brother."
Promoters Queensberry Promotions said once doctors have assessed the cut they will have a "better idea of the recovery period needed".
IBF mandatory challenger Croatian Filip Hrgovic, 31, told ESPN: "Now that Fury [is] injured, I'm ready to step in and fight Usyk.
"Let's go Usyk, you owe me my mandatory shot. It's time to finally face me."
The fight was originally scheduled for 23 December but Fury's controversial decision win over former UFC fighter Francis Ngannou in October scuppered those plans.
Morecambe-born Fury has won 34 fights with one draw since turning professional in 2008.
He had previously faced criticism for failing to reach terms with Usyk after a proposed bout at London's Wembley Stadium in April fell through.
Analysis - Is this just a bump in the road for Fury v Usyk?
Kal Sajad, BBC Sport
With just over two weeks to go, the majority of the media already had their flights and hotels booked for this bout.
This is boxing - injuries and cuts are always a danger and both teams will be keen on rescheduling the fight, perhaps for the summer. But what does that mean for the heavyweight landscape?
There are reports Tyson Fury could be replaced by Croatian Filip Hrgovic, the mandatory challenger for Oleksandr Usyk's IBF belt.
Then we have Anthony Joshua v Francis Ngannou in Riyadh on 8 March. Saudi organisers wanted the winner of that fight to challenge for the undisputed title.
Perhaps this is just a little bump in the road, but bureaucracy and politics have stopped big fights from happening in recent years - fans have become used to disappointment and will be greatly pessimistic about seeing Fury v Usyk.
This news has sent shockwaves through the sport; an almighty blow to the hopes of millions of fans who were so desperate to find out who is the best heavyweight on the planet.
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