New Zealand hooker Dane Coles has been ruled out of Saturday's Test against Australia, with coach Steve Hansen confirming he is again suffering a possible head injury.

Soon after arriving in Sydney on Sunday afternoon, the All Blacks tweeted that Coles would not be considered for the Test, the first in the Rugby Championship.

Hansen said Coles left the field "as a precaution" during last Friday's game against Counties Manukau and Taranaki in New Zealand, and would be assessed by the All Blacks medical staff while in Sydney this week.

Coles, with 49 Tests under his belt, is New Zealand's first-choice hooker. But he missed most of the Super Rugby season and the three Tests against the British and Irish Lions because of concussion symptoms following a head knock in March.

His Wellington Hurricanes team-mate Ricky Riccitelli has been summoned to Sydney as a replacement.

Source: AFP