The bout was originally scheduled to take place in Brisbane, Australia, on November 24.

Thinus Strydom, of World Sport Promotions, said on Wednesday the fight had been rescheduled after Williams underwent surgery on his pectoral muscle on Tuesday.

“We wish Williams a speedy recovery and hope that he is able to return to training soon,” Strydom said.

“It’s likely that the bout will now take place in February.” 

Williams, who is the New Zealand heavyweight champion, picked up the injury while playing for the Japanese rugby team, the Wild Knights, last week.

Botha, who is the former IBF world heavyweight champion, had sent a warning to Williams ahead of the fight.

“I’ve seen him as a boxer in the few fights that he’s had, and all I can say is he’s in for a rude awakening.” 

Speaking at the launch of the fight in Durban last week, the 44-year-old South African said: “He’s going to be hit harder than he’s ever been before. If I was in his shoes, I’d be shaking.”

The surgery also looks likely to delay his return to Japanese rugby.

His Panasonic Wild Knights club told Reuters they were discussing a rehabilitation schedule for the 27-year-old but were not sure when he would return to Japan from Australia.

“It’s not been decided where and what kind of rehab programme he will undergo,” team manager Seigo Ikeda said. “We want to work out those details quickly obviously.”

Williams wrote on his Twitter page: “Just spoke to the doctor operation went well, Thanks for the support I’ve truly been blessed.”

The hulking centre injured his shoulder and chest while playing for Japanese Top League club Panasonic at the weekend.

He smashed his shoulder into the turf after a tackle in Panasonic’s 23-20 win over Kintetsu Liners on Saturday and was rushed to hospital for an MRI scan.

The injury could spell a premature end to his Japanese season with Panasonic having seen little return halfway through their investment.

Williams is expected to quit union and return to rugby league with the Sydney Roosters next year.