Former WBA heavyweight champion David Haye has pulled out of his proposed 29 June bout with Manuel Charr due to a hand injury sustained in training.
The Briton had hoped a strong showing against Lebanon-born German Charr, 28, would help set up a world title fight with one of the Klitschko brothers.
It is not yet clear whether the fight, which was scheduled for the Manchester Arena, will be rearranged.
"I'm absolutely gutted to have to pull out of this fight," said Haye, 32.
"I need to rest it up for at least four weeks. I pick up injuries now and again in training, and sometimes carry them into fights, but this was one I simply couldn't recover from in time.
"I apologise to Manuel Charr and to everybody involved with the promotion. But most of all I want to say sorry to the thousands of fans who bought tickets to the fight. I felt it was important to let them know about the cancellation as soon as possible, so they can now make other plans.
"As soon as I am told I can resume full training, my loyal fans will be the first to know."
Haye, who has injured his left hand, has not fought since beating Dereck Chisora last July.
Haye reversed that decision to fight Chisora before revealing in March that he would fight again.
He previously won the WBA belt by beating giant Russian Nikolay Valuev on points in Germany in November 2009.