Everton midfielder Dan Gosling has been ruled out for up to nine months with a knee injury, the club have announced.
The 20-year-old was hurt in a collision with Wolves goalkeeper Marcus Hahnemann late in Saturday's goalless Barclays Premier League draw at Molineux.
Physio Mick Rathbone told the club's website: "Our worst fears have been confirmed. Dan has ruptured his cruciate ligament and will unfortunately be out for up to nine months."
Gosling had only entered the action as an 83rd-minute substitute and was attempting to score a late winner when he collided with Hahnemann.
The England Under-21 international has scored three goals in 17 first-team appearances this season.
Everton have been hampered by injuries throughout the campaign.
Mikel Arteta, Phil Jagielka and Victor Anichebe only recently returned after near year-long absences while Phil Neville, Tony Hibbert, Joseph Yobo and Leon Osman have all endured lengthy lay-offs during the campaign.
Marouane Fellaini is currently sidelined after being ruled out for the season with an ankle injury suffered in the Merseyside derby in February.
Manager David Moyes said: "I'm really disappointed for Dan. He's been making great progress here at Everton and we look forward to having him back as soon as possible."
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