Boxing All Black Sonny Bill Williams had successful surgery on a chest injury in Sydney on Wednesday.
The 27-year-old announced the news on Twitter a day after arriving from Japan, where he picked up the pectoral injury playing rugby union for the Panasonic Wild Knights last weekend.
"Just spoke to the doctor operation went well, Thanks for the support I've truly been blessed," tweeted Williams.
With Japanese rugby on a five-week break, Williams initially flew to Sydney to prepare for a boxing bout next month.
But it was rumoured that the dual international was also poised to formally sign a contract to return to rugby league with the Sydney Roosters.
Instead, Williams went straight to the NRL club's headquarters at Moore Park to undergo scans on an injury that could threaten or at least delay his high-profile switch back to the code after walking out on the Bulldogs in 2008.
Reports on Tuesday night suggested Williams was set to be out of action for at least two months.
The injury puts in jeopardy his return to the Wild Knights, where he is contracted until the end of January, while his heavyweight fight with South African veteran Francois Botha on November 24 will almost certainly be postponed.
And while his mooted deal with the Roosters might still eventuate, the untimely injury has the potential to further complicate negotiations that have been bubbling away for months.
In July, Williams said he would quit the All Blacks to fulfil a handshake agreement made several years ago to return to rugby league in the NRL in 2013.