TOKYO (Reuters) - Boxing All Black Sonny Bill Williams had surgery on a pectoral injury on Wednesday, which looks likely to delay his return to Japanese rugby and force the postponement of his next fight.

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.

Also New Zealand's heavyweight boxing champion, Williams flew to Sydney on Tuesday to prepare for his November 24 bout with 44-year-old Francois Botha in Brisbane.

However, Williams now faces up to two months out, which would leave little option but to postpone the fight, while his return to Japanese rugby could also be in doubt.

"We have been in contact with his agent and they want to hear medical opinions before deciding, perhaps also talk to All Blacks or (Waikato) Chiefs staff," Ikeda added.

"We want what's best for the player. We're not concerned he won't return. He has a contract. What's important is to find the best way for him to get fit again."

Williams left the world champion All Blacks and Waikato Chiefs for a lucrative 12-match deal in Japan worth an estimated $100,000 a game.

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.

(Editing by John O'Brien)

• Please wait.

• Sarawakian Daniel makes a winning return from injury
• ‘Comeback king’ Timothy lands his second title
• Pistorius rules out track return this year - report
• Seven more Al Zarooni horses test positive
• Lowe reunited with Hamilton at Mercedes
• F1 tyre changes to be less dramatic than feared
• Golf: Johnson triumphs by one stroke at Mobile Bay LPGA
• Results worldwide
• Bradley clings to lead in Texas with surging Korean one stroke adrift
• Classy Williams sweeps Azarenka aside in final