New Zealand fly-half Dan Carter has emerged as a doubt for Saturday's Test clash with Wales at the Millennium Stadium.
Test rugby's leading points scorer pulled up in training on Thursday and will be assessed by the All Blacks' medical staff on Friday.
The 30-year-old was named in the starting line-up for the Cardiff match after being an unused replacement in last week's 42-10 victory over Italy.
With Beauden Barrett sidelined with a rib injury, Aaton Cruden is on standby to step up from the bench should Carter not be considered fit enough to start.
Carter missed the latter stages of the All Blacks' victorious World Cup campaign last year with a groin problem and it is hoped this is not a repeat of the same injury.
New Zealand are bidding to extend their unbeaten run over the Welsh which stretches back to 1953.
Who will win when Wales face New Zealand on Saturday?