Blues regular captain and ten year All Blacks veteran Keven Mealamu could miss the All Blacks test match series against Ireland due to injury.
Mealamu has not played Super Rugby since he limped off against the Sharks early in April and has only played in six matches and was subbed in three of those.
The Test hooker has been plagued by a series of calf injuries which have kept him out of the Blues line up.
Mealamu was expected to return to the Blues line up on a couple of occassions but this has not materialised.
All Blacks coach Steve Hansen has now revealed that the 92-test hooker re-injured his his calf two weeks ago and the coach and his fellow selectors were waiting to see the results of further scans.
Hansen said that they had also been watching how Mealamu coped with the first day of the extended squad's training camp.
"Kevvie is a bit of a worry with that calf, there may be an issue arising there," Hansen told the NZHerald.
"Clearly if things don't go well we will have to bring in another player."
Hansen and his fellow selectors Ian Foster and Grant Fox did not name a third hooker in their All Black squad as they thought Mealamu and Andrew Hore would get through three June tests against Ireland.