Rugby: Sonny Bill Williams stays with All Blacks for 2019 World Cup

Sonny Bill Williams speaks to the media after it was announced that he has signed a three year deal with the New Zealand Rugby Union and will play for the Auckland Blues next year. PHOTO: AFP

WELLINGTON (AFP) - Cross-code superstar Sonny Bill Williams has confirmed that he will stay with the All Blacks until late 2019, rejecting lucrative offers from overseas clubs and rugby league to chase his third World Cup title.

Williams, who is currently playing rugby sevens with hopes of snaring a medal at the Rio Olympics, said he wanted to remain part of the All Blacks' winning culture.

"I love winning. I love the high-pressure environment. I don't know if I could get that overseas," the 30-year-old told reporters on Wednesday.

While his athletic prowess is unquestioned, he has been criticised as a dilettante for only signing one-year deals that let him flit between rugby union, league, sevens and boxing.

The three-year contract is his longest commitment to the All Blacks and coach Steve Hansen said it would give him the chance to etch his name in union's honour roll.

"He'll only get better and better. He could end up being one of the greats of our game," Hansen said.

Under the deal, Williams will switch his Super Rugby allegiance from the Waikato Chiefs to the Auckland Blues, coached by former All Black great Tana Umaga.

"It's no secret that Tana and I go way back," said the 33-Test centre, who worked with Umaga at Toulon when he first switched to union in 2008 then again at Counties Manukau in 2014.

"I feel like I'm coming home," added Williams, who was a member of New Zealand's 2011 and 2015 World Cup-winning squads.

During his much-travelled career, he has also won both the Super Rugby title with the Chiefs and the Rugby Championship with New Zealand.

In rugby league, he won Australia's NRL twice, with the Bulldogs in 2004 and Roosters in 2013, while Williams also triumphed in all seven of his professional heavyweight boxing bouts, even winning the New Zealand title in 2012.

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