Montpellier - New Zealand international flyhalf Aaron Cruden will miss two to three weeks due to a knee injury, his club Montpellier said on Monday.
The 28-year-old was hurt in a tackle by Matt Smith while providing the final pass for a try by Henry Immelman in the 68th minute of Saturday's 36-26 victory over Glasgow.
Cruden was forced off and underwent an MRI scan on Monday, which revealed a bruised bone.
The former All Black, who has won 50 caps, will miss the visit of Lyon on Saturday as well as the trip to Brive on December 30.
He could make his return to action against Stade Francais on January 6.
South African centre Francois Steyn or versatile scrumhalf Benoit Paillaugue could replace Cruden in the No.10 jersey.
Otherwise, New Zealander coach Vern Cotter could turn to inexperienced young fly-half Thomas Darmon.