Northampton full-back Ben Foden has been ruled out for the rest of the season with a ruptured anterior cruciate ligament in his left knee.
Foden picked up the injury and left the field in the 12th minute of Northampton's 20-9 European Champions Cup victory over Ospreys in Swansea on Sunday and scans revealed the severity of the injury.
He had been in the frame to be called up to England's 34-man Six Nations squad which will be announced on Wednesday.
Instead, he will undergo surgery and rehabilitation in the hope of returning ahead of the 2015/16 season.