Alex Corbisiero will miss England's autumn Tests after suffering a shoulder injury.
The Northampton prop was hurt during Saints' 31-24 Aviva Premiership victory over Bath at Franklin's Gardens last Saturday.
And Northampton have now announced that he will be sidelined "until early 2015" due to a ligament tear.
Corbisiero, 26, has had a recent history of serious knee trouble, and this latest setback will come as a major blow for both his club and England head coach Stuart Lancaster.
In a statement, Northampton said: "Northampton Saints has today announced that Alex Corbisiero has sustained a ligament tear to his shoulder that will keep the England prop out of action until early 2015.
"Corbisiero sustained the injury in the second half of the Saints' Aviva Premiership round four 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."
