Everton striker Cenk Tosun will undergo surgery on an anterior cruciate ligament injury next week.
The Turkey international returned from a loan spell at Crystal Palace after sustaining the damage in training on Monday and now faces a lengthy absence after surgery.
"The player will continue his rehabilitation under the care of Everton's medical staff at the club's USM Finch Farm training headquarters following the surgical procedure on his ACL," said an Everton statement.
Tosun scored 10 goals in 51 appearances for Everton but has played just five times for Palace since his temporary January move to Selhurst Park.
"Sometimes everything in life doesn't go the way you want it. However, it is not the first time," Tosun wrote on Twitter.
"It's not about falling to the ground, it's about being able to get back on your feet after falling to the ground.
"I don't want anyone to doubt that I'll be back in the strongest possible way from this injury."
Manager Carlo Ancelotti has received some good news, however, with left-back Lucas Digne training again having missed the last two matches with a muscle problem.
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