Tyson Fury says an ankle injury has forced him to postpone next month's rematch with Wladimir Klitschko.
Fury was scheduled to defend his WBA and WBO heavyweight belts on July 9 against the man he dethroned in 2015 after 11 years at the top.
But the champion posted a social media message on Friday revealing a badly-sprained ankle will mean a new date further down the line.
"About 10 days ago I was running in the Lake District and went over on my ankle," said Fury, who was critical of Klitschko for postponing their first fight and twice before that saw injuries to David Haye scupper world title shots.
"I've had x-rays and MRI scans and all that stuff, and they said it's not broken but badly sprained and to keep off it for six or seven weeks.
"I tried to still train a bit, but I had a second opinion a week later and had the same advice, so the fight will be postponed.
"Sorry to all my fans to let you all down, but injuries do happen and it's one of those things. Apologies to everyone who's booked dates, but the fight will be on as soon as possible.
"That's all I know at the moment, but the fight's still going ahead. As soon as the ankle's better we will reschedule."
Fury's trainer and uncle Peter posted a picture of Tyson's badly-swollen ankle on his Twitter page and said a date for the rescheduled fight - still at the Manchester Arena - would be announced soon.
Klitschko is understandably upset to have his chance at redemption put back and hopes Fury's injury will not mean too much of a delay.
He said: "Of course I am currently totally disappointed about the cancellation.
"As well for my fans I'm very sorry who were all very excited for this rematch. But one thing is also clear: Then I'll get my belt a few weeks later."
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