Gosling raptured his cruciate ligament in the goalless draw with Wolves last weekend.
“Our worst fears have been confirmed,” Everton physio Mick Rathbone told the club’s official website.
“Dan has ruptured his cruciate ligament and will unfortunately be out for up to nine months.”
“I’m really disappointed for Dan,” said Everton boss David Moyes. “He’s been making great progress here at Everton and we look forward to having him back as soon as possible.”
