Dane Coles' persistent concussion issue could force him to miss all three of New Zealand's Test matches against the British and Irish Lions.
That was the verdict handed down by All Blacks coach Steve Hansen after he named a 33-man squad on Thursday which featured several injured players.
Star hooker Coles, who has not played since March, is among them, while the likes of Kieran Read, Liam Squire - both of whom have broken a thumb - and Jerome Kaino (knee) are also fitness doubts.
"Just to clear up some of the things, the injury replacements are there because obviously Dane Coles is suffering from concussion," said Hansen.
"More than likely that he's not going to be available at least for the first couple of Tests anyway.
"And our loose forward trio, two of them [Kieran Read and Liam Squire] have broken thumbs. Both are looking to be fit hopefully for the first Lions test.
"JK's [Kaino] hoping to be on the track next week against Samoa but in the need for good preparation, we need to bring players in just in case something goes wrong there."
Uncapped Hurricanes duo Jordie Barrett and Ngani Laumape were included in Hansen's selection, with the first Test taking place in Auckland on June 24.