Wellington - New Zealand flank Victor Vito will miss Saturday's second Test against Ireland with a knee injury and might be sidelined for five weeks.
Adam Thomson, who replaced Vito when he limped from the field during New Zealand's 42-10 first Test win, will start in the No 6 jersey in the match at Christchurch.
Vito will also miss the third Test at Hamilton on June 23 and Chiefs flank Liam Messam is on standby to join the squad.
Meanwhile, All Blacks coach Steve Hansen said hooker Keven Mealamu had recovered from the calf injury which kept him out of the first Test and was fit to play on Saturday.
But Mealamu's return is likely to be delayed until the third Test to allow him further training time after he was forced to miss six weeks of Super Rugby.
The 33-year-old Mealamu has played 92 Tests and needs one more to overtake Sean Fitzpatrick as New Zealand's most-capped Test hooker.
"He's fit to play if loose on the we want him to," Hansen said. "But we are going to give him a week of full training and get his body used to that first. Then we might let him paddock next week."
New Zealand trained in bitterly cold conditions on Tuesday and similar conditions are forecast for Saturday.