Cenk Tosun will return to Everton following surgery to repair a patella tendon injury suffered on loan at Besiktas.
Tosun, who returned to his former club on loan in January, landed awkwardly in the 70th minute of the win over BB Erzurumspor in the Super Lig on Sunday and was stretchered off.
An Everton statement released on Monday read: "Cenk Tosun has undergone surgery in Turkey after rupturing his patella tendon while playing for loan club Besiktas.
"The Everton striker sustained the knee injury on Sunday and following the operation he will return to USM Finch Farm to be assessed by the club’s medical team.
"Tosun was due to spend the rest of the 2020/21 season on loan at Besiktas, the Turkish club he spent four years with before signing for Everton in January 2018."
Tosun will now face a race against time to be fit to represent Turkey at the rearranged EURO21 Championship this summer.
Tosun cost £27m when he arrived at Everton under the management of Sam Allardyce.
He had played only three times for Besiktas - scoring three goals - since returning in January after picking up a knee injury which ruled him out for four matches.
Tosun is contracted at Everton until the summer of 2022.
