Former light heavyweight titlist Nathan Cleverly, due to make his cruiserweight debut Saturday at the Copper Box Arena in London, dropped out of his fight Tuesday because of a back injury.
The 26-year-old Cleverly (26-1, 12 KOs), of Wales, was scheduled to fight 30-year-old Australian Daniel Ammann (29-5-1, 6 KOs) for the vacant Commonwealth title on the undercard of European heavyweight champion Dereck Chisora's first defense against Ondrej Pala.
Cleverly hurt his back last week while training and said he was advised to withdraw from the bout.
"It's a bitter blow as training had been going so well, and I was looking forward to making my debut at cruiserweight," Cleverly said. "For it to only happen a week before the fight is even more devastating. I just want to get this year out of the way and enter 2014 with a clean slate and get my career back on track."
Cleverly made five successful defenses of his light heavyweight title before Sergey Kovalev went to Wales and was dominant in a fourth-round knockout victory Aug. 17.
When Cleverly was getting set for his return, he announced that he would move up to the 200-pound cruiserweight division.