Crusaders captain Kieran Read will miss his team's Super Rugby match against the Brumbies in Christchurch after he was forced to withdraw from the squad due to concussion.
Read was hoping to be declared fit to return for the Crusaders but failed to convince the medics that he had fully recovered from the head knock he sustained playing against the Chiefs before the bye.
This will be the second time this season that Read has had to withdraw from the Crusaders as he failed a concussion test in the March match against the Hurricanes and missed the match against the Lions a week later.
The IRB have cracked down on concussion testing and instructed medics and coaches not to consider players who have the mildest of concussions symptoms.
All Blacks coach will be concerned that Read is missing another match especially since the Crusaders played the Chiefs two weeks ago and Read has not fully recovered despite having the week off due to the bye.
Read's withdrawal could see All Black captain Richie McCaw make his return to Super Rugby at No.8 after a two month lay off due to a broken thumb.