All Black centre Conrad Smith has withdrawn from the Rugby Championship and Bledisloe Cup opener against Australia in Sydney.
Hurricanes captain Smith has returned to New Zealand from Australia to be by his wife's side for the birth of his child.
"Conrad Smith has returned to NZ to be with his wife who is expecting a baby. Ryan Crotty called into AB squad as cover," the All Blacks announced on their Twitter account.
Smith has won 77 caps with New Zealand's All Blacks and has formed a powerful partnership with centre Ma'a Nonu.
The loss of Smith is a blow for the All Blacks as they are in search of a record-breaking 18th consecutive win.
Highlanders centre Malakai Fekitoa is expected to replace Smith with Crotty filling in for Fekitoa on the replacements bench.