Chelsea midfielder Michael Essien will be out of action for at least five months after rupturing an anterior cruciate knee ligament.
"I spoke to Michael and he's obviously had a bad injury," Chelsea captain John Terry told a news conference in Zagreb ahead of England's World Cup qualifier against Croatia.
"He was saying it was like five or five and a half months."
The Chelsea website said Essien had sustained the injury playing for Ghana against Libya in a World Cup qualifier last Friday and would undergo surgery once the swelling had subsided.