Tyson Fury's rematch with Wladimir Klitschko has been postponed for the second time.
The pair were due to meet in Manchester on October 29, with Morecambe’s world heavyweight champion defending the WBA and WBO belts he took off Ukrainian Klitschko last November.
One attempt at a rematch had already been abandoned because of an ankle injury sustained by Fury, and his management cited medical reasons behind the latest cancellation.
"It is with the deepest regret that we have to announce that the world heavyweight championship rematch between Tyson Fury and Wladimir Klitschko, scheduled to take place on the 29th October 2016 at the Manchester Arena, will not be going ahead," a statement read.
"Tyson has, this week, been declared medically unfit to fight. Medical specialists have advised that the condition is too severe to allow him to participate in the rematch and that he will require treatment before going back into the ring. Tyson will now immediately undergo the treatment he needs to make a full recovery.
"We and Tyson wish to express our sincerest apologies to all those concerned with the event and all the boxing fans who had been looking forward to the rematch. Tyson is understandably devastated by the development."
After Fury's injury shelved the July 9 date it then emerged that UK-Anti Doping (UKAD) had charged the champion, over a urine sample taken in February 2015, and his cousin Hughie with a doping offence.
It was alleged the sample - taken nine months before his defeat of Klitschko - contained traces of the banned substance nandrolone.
Fury was provisionally suspended, but that ban has since been lifted, and his legal team said they would be suing UKAD over the allegations. His hearing will be held in November.
The 28-year-old was last week due to attend a press conference with Klitschko, but failed to show up, with his manager citing car problems.