Sonny Bill Williams will be a Chief in 2012 but it won't stop him boxing.

Williams kept everyone guessing right up to yesterday's deadline before being confirmed by the New Zealand Rugby Union as having re-signed for one more year and nominating the Chiefs as his new team.

He parted ways with the Crusaders, for whom he played in this year's Super Rugby competition, in order to move closer to his mother in Auckland and then turned his back on overseas offers that had threatened to take him offshore after he struggled to get starts for the All Blacks during the recent Rugby World Cup.

Williams' new contract allows him to fight two boxing bouts – one during pre-season and one during the week of one of the Chiefs' two byes, which fall on the weekends of March 23-25 and May 18-20.

That mirrors the deal he had while playing for the Crusaders when he fought one bout in January and one in June this year.

But new Chiefs head coach Dave Rennie saw no problem with those commitments, saying they would not interfere with his training for the team and were pivotal to him staying in New Zealand.

"Obviously he could earn massive sums of money playing footy overseas but he's really keen to do different things as well as coming here to make a difference," Rennie said.

"One [bout] will happen in pre-season and one will be during one of the bye weeks and the big thing is it won't have an impact on his playing for the team.

"He's fully committed to that and if he's doing a bit of boxing training as well he'll be in pretty good nick for us."

Rennie said the Chiefs had looked closely at the dangers of any distractions the publicity constantly generated by Williams might provide the team but he had been assured by his new assistant coach and departing All Blacks assistant Wayne Smith that Williams was "very professional, very dedicated, has a fantastic work ethic and wants to be better and go well".

Williams left New Zealand for an overseas holiday on Sunday, via Australia, and although held up by the Qantas strike, hinted on Twitter he was going to Panama.

He also yesterday tweeted a hint at his decision with the words "I hear Hamilton is nice".

That was enough to ease the mind of Chiefs chief executive officer Gary Dawson, who admitted he was less than optimistic earlier in the day about his franchise's chances of getting Williams' services.

Dawson said he had not played a direct part in the negotiations with Williams' manager Khoder Nasser, but Chiefs contracts manager Chris Tindall had been involved alongside the NZRU negotiators.

"We're thrilled that he's coming to the Chiefs and we think that he will make a fantastic contribution to the team," Dawson said.

"He's obviously a very talented player and with his ability and our coaching staff we hope we're going to see the very best of him in 2012."

While Williams will be an obvious promotional drawcard and likely boost to ticket sales for Chiefs' home games, the first of which is on February 25 against the Highlanders, Dawson said the most important thing for him was the contribution the player made on the field.

"We are building a new team and are looking to him to make a big contribution to it," Dawson said.

Sonny Bill Williams

Born: August 3, 1985 in Auckland

Physical: 1.91m, 110kg

Major teams: Canterbury Bulldogs (2004-08), Kiwis (rugby league); Toulon (2008-10), Crusaders (2011), All Blacks, Chiefs (2012)

Super rugby appearances: 15

Points: 25

All Blacks test debut: v England, Twickenham, November 2010

Tests: 14

Points: 20

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