Dan Carter is a major doubt for New Zealand's Test against Ireland after he suffered an Achilles injury during the win over England.
The fly-half won his 100th cap in the 30-22 victory at Twickenham but had to be replaced after just 26 minutes.
Carter could be ruled out of next weekend's clash at the Aviva Stadium, where the All Blacks will bid to become the first international side in the professional era to enjoy a perfect calendar year as they aim for a 14th straight win in their final match of 2013.
"He's hurt his Achilles (tendon)," said New Zealand coach Steve Hansen. "It's the other one, not the one he damaged years ago.
"It's been rumbling for a while but it's not ruptured, I don't think.
"It's disappointing for him again, he'd had a wretched time but he made a major contribution when he was on."
Richie McCaw presented Carter with a special silver cap to mark his 100th Test appearance and the New Zealand captain hailed him as "one of the greats".
"He's obviously very proud to play 100 Tests and would have loved to have been out there for 80 minutes but he's got that milestone and got a bit of a smile on his face," said McCaw.
"His contribution has been phenomenal. I've played alongside him for a lot of those Tests. The calm head he has, it makes my job a lot easier.
"We take for granted how good he is, we expect great things every time and he's one of the reasons the All Blacks have had so much success in recent years."