All Blacks centre Sonny Bill Williams is under an injury cloud ahead of the Bledisloe Cup decider.
All Blacks coach Steve Hansen revealed Williams fell heavily on his tailbone about 20 minutes into the Rugby Championship.
He is unlikely to train with the team.
The Wallabies won the Rugby Championship after beating the All Blacks 27-19 in Sydney over the weekend.
The All Blacks play the Wallabies at Eden Park at 7.35pm this Saturday.