Not for the first time Williams, 28, is leaving others to speculate as to his next sporting move after helping the Sydney Roosters to NRL Grand Final victory on Sunday, but it won’t be wearing the black and white of the Kiwis when the Cup kicks off later this month. 

A return to rugby union is the most likely option, although another tilt at boxing glory has also been suggested.

Williams missed the 2008 World Cup after deserting the Canterbury Bulldogs for rugby union and went on to win the 2011 World Cup with the All Blacks.

“Sonny is unavailable due to other commitments,” Kiwi coach Stephen Kearney said. “What they are at this stage, I’m sure we would all like to know and I’m sure we will hear all about that over the next two or three weeks.”

Reports since Kearney’s comments have suggested Williams could backflip on his decision, but no party has confirmed this either way.

Nevertheless, four of Williams’ co-Roosters will line up for Kearney’s side, including Sam Moa (who has changed allegiance from Tonga, the nation he’s represented eight times).

Winger Roger Tuivasa-Sheck makes his debut NZ squad in place of Shaun Kenny-Dowall, whose jawwas broken in the grand final.

Benji Marshall, another high-profile Kiwi figure and former skipper, is also absent after signing with Super Rugby’s Auckland Blues.

Simon Mannering will captain the side when they warm up against the Cook Islands at Keepmoat Stadium, Doncaster, on Sunday, October 20.

Their opening group game is against Samoa on October 27. New Zealand also face France and Papua New Guinea before the play-off stage.

New Zealand: Jesse Bromwich (Melbourne Storm), Greg Eastwood (Canterbury Bulldogs), Kieran Foran (Manly Sea Eagles), Alex Glenn (Brisbane Broncos), Bryson Goodwin (South Sydney Rabbitohs), Tohu Harris (Melbourne Storm), Josh Hoffman (Brisbane Broncos), Krisnan Inu (Canterbury Bulldogs), Shaun Johnson (NZ Warriors), Sam Kasiano (Canterbury Bulldogs), Thomas Leuluai (NZ Warriors), Kevin Locke (NZ Warriors), Issac Luke (South Sydney Rabbitohs), Simon Mannering (NZ Warriors), Ben Matulino (NZ Warriors), Sam Moa (Sydney Roosters), Jason Nightingale (St George Illawarra Dragons), Frank-Paul Nu’uausala (Sydney Roosters), Frank Pritchard (Canterbury Bulldogs), Elijah Taylor (NZ Warriors), Roger Tuivasa-Sheck (Sydney Roosters), Manu Vatuvei (NZ Warriors), Jared Waerea-Hargreaves (Sydney Roosters), Dean Whare (Penrith Panthers).

Images via Getty