Rugby World Cup 2019: Midfield mix looms as All Blacks' toughest selection

Ma'a Nonu and Sonny Bill Williams could end up fighting for the last spot in the All Blacks World Cup midfield, after coach Steve Hansen gave both veterans ringing endorsements.

The battle for the inside-centre jersey is the most intense of any facing Hansen, as he weighs up the merits of some highly accomplished performers against Blues stalwarts Nonu and Williams, who were involved in New Zealand's triumphant campaigns of 2011 and 2015.

Nonu, 36, also played in the 2003 World Cup, in the formative stages of a 103-test career.

The 2015 final at Twickenham was thought to be his swansong, but after three seasons with French club Toulon, he has produced compelling displays in the last two rounds of Super Rugby.

Hansen acknowledged Nonu's form, before explaining why he wasn't included in a 41-strong player 'foundation day' in Wellington on Monday.

He said it had been previously decided that only players contracted in 2018 would take part.

"There's some guys who aren't here that, if you were picking it on form, probably would be here," he said.

Hansen admitted he faced a headache at inside centre, given Ryan Crotty, Anton Lienert-Brown and Ngani Laumape were also in excellent nick for their Super Rugby teams.

Nonu had thrust himself into the mix.

"None of us knew what Ma'a was going to come back like," Hansen said.

"He's just being Ma'a, isn't he? You're getting the subtle touches and you're getting the brutality.

"We know he can play test rugby. He's just got to show us he's got the ability to do that on a weekly basis at 'Super' level - then we have to make decisions."

Cross-code star Williams underwent knee surgery last week and will be sidelined for another month, adding to a litany of ailments over the last two years.

Hansen said the 33-year-old boasted attributes and experience that made him invaluable.

"If he gets back and plays four or five games, bingo, he's going to play some good footy, isn't he?

"It's just a matter of staying on the park. Once he's shown he can do that, he's going to be a hard man to leave out."

AAP 

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