Billy Joe Saunders has withdrawn from his WBO middleweight title defence against fellow Englishman Martin Murray through injury.
The fight had been due to be held at London's 02 Arena on June 23.
It is the second time the fight has been postponed this year after Saunders had earlier injured his hand in training.
"Due to injury I had to withdraw from the 23rd, you have your ups in boxing but last 3 months been downs," Saunders said on his personal Twitter account on Sunday.
"Sorry to Martin and the fans, be back soon."
The 28-year-old Saunders, who is unbeaten in 26 fights, would have been making the fourth defence of a title he won in December 2015.
Saunders' promoter Frank Warren tweeted: "A full statement on the show will be made tomorrow (Monday).
"We apologise for any inconvenience."
Murray posted a video on social media saying that he had been told the fight was off as Saunders had suffered a hamstring injury.
"I am obviously gutted, but there's nothing I can do," Murray said.
"I just want to apologise to everyone who's bought tickets, booked hotels and train fares, and just say thank you for your continued support and believing in me.
"My management team is working on an alternative, so hopefully I'll have a new date in the next couple of weeks."