The All Blacks have confirmed that Dan Carter is out of the Rugby World Cup because of a groin injury.
All Blacks doctor Deb Robinson and coach Graham Henry gave a medical update on Carter on Sunday morning at the team's hotel in Wellington.
Ms Robinson said he has torn the adductor longus tendon in his left groin.
The injury is severe and surgery is a possibility.
Ms Robinson said the "best guess" would be that Carter would be out for about 10-12 weeks.
Carter, 29, pulled the groin muscle during kicking practice. Television images showed him limping during a light training run in Wellington on Saturday.
He was due to captain the All Blacks for the first time on Sunday in a pool match against Canada, in the absence of Richie McCaw, who has a foot injury.
Colin Slade will replace him at first five and hooker Andrew Hore will lead the team. Aaron Cruden will be brought into the squad.
Slade, 23, has produced mixed performances in his appearances to date.
Rugby commentator Keith Quinn earlier said it's a crisis for the All Blacks at the business end of the tournament.
McCaw and Carter were considered integral to New Zealand's chances of winning the tournament this year, for the first time since the inaugural event in 1987.
Carter has played 85 Tests. He will travel to Auckland with the rest of the squad for further diagnosis.
"I think it's pretty obvious this is a major (blow),'' said coach Graham Henry.
"This was going to be his pinnacle and it's devastating for him. This was his scene, this World Cup in New Zealand and it was going to be his big occasion.
"I feel very sad for him but he is the type of guy who will handle this. He has strength of character ... and I feel huge sympathy for him."
Carter is no stranger to serious injury. In late January 2009, he ruptured his achilles tendon while playing for the Perpignan club in France during a six month sabbatical.
But he recovered more quickly than expected and turned out for Canterbury before playing for New Zealand again in August that year.
Carter tweaked his back before the All Blacks' second World Cup pool match and sat out the Japan pool game in Hamilton.