Northampton Saints have confirmed that England prop Alex Corbisiero will be out of action until "early 2015" with a serious shoulder injury.
The 26-year-old suffered ligament damage on Saturday during his side's win over Bath in the Aviva Premiership.
The injury will keep Corbisiero out of England's upcoming Autumn Internationals, while his participation in next year's Six Nations could also be under threat.
An official Northampton statement read: "Corbisiero sustained the injury in the second half of the Saints' Aviva Premiership Round 4 game against Bath, with the specialist's advice being that the tear needed surgical repair so that he can play to an optimum level in the future. The Saints and England medical teams are liaising on Corbisiero's treatment and recovery."
Northampton return to Aviva Premiership action on Saturday with a trip to London Irish.