Australia flanker David Pocock has been ruled out this summer's Test series with the British & Irish Lions after sustaining a serious knee injury.
Pocock, 24, will be out for six months after rupturing a cruciate ligament in Brumbies' 35-6 Super 15 win over the Waratahs on Saturday.
He will have surgery this week and is set to miss the Lions matches.
"To hurt my knee so early in the season is obviously disappointing," Pocock told the Brumbies website.
Pocock is renowned as one of the finest openside flankers in the world and was expected to play a key role in Robbie Deans' plans.
Deans had previously stated that the 2013 captaincy would be decided between World Cup skipper James Horwill and Pocock.