Bournemouth's England midfielder Lewis Cook will be sidelined for six to nine months with a ruptured anterior cruciate ligament, the club have announced.
The 21-year-old suffered the serious knee injury during the 2-1 Premier League victory over Huddersfield on Tuesday.
Cook was assessed by the club's medical staff after the game and further assessment and scans on Wednesday revealed the extent of the damage to his right knee.
Lewis Cook has ruptured his ACL and will now miss six-to-nine months. Our thoughts are with you, @lewiscook_.#afcb 🍒https://t.co/ekIqRnMr7h
— AFC Bournemouth (@afcbournemouth) December 6, 2018
"We are all devastated for Lewis," Bournemouth manager Eddie Howe told the club's official website.
"It is a huge blow to a very talented player who has been a very important part of our side over the last 18 months.
"But Lewis is a strong character who only has to look around our dressing room for inspiration of how an injury like this is merely a setback and to know that he can come back better than ever.
"He will have the full support and love of everyone at the club throughout the next few months as he receives the very best treatment and rehabilitation possible."
Cook has made 56 appearances since joining Bournemouth from Leeds in July 2016, with 15 of those coming this season as the Cherries have climbed into the top seven of the Premier League.
York-born Cook captained England to Under-20 World Cup glory in 2017.
In doing so, Cook became the first England captain to lift a world trophy since Bobby Moore in 1966.
Cook won his first senior England cap as a substitute in the 1-1 friendly draw against Italy at Wembley in March.
