The left-back has not played since suffering a hamstring injury in February and now a similar concern picked up during training will see him at least miss the club’s pre-season tour of Asia.
Sessegnon was at the time initially ruled out for six weeks but failed to make another appearance for the remainder of the season, and this latest injury will be another concern for both player and club.
A statement read: “Ryan Sessegnon has undergone surgery to his left hamstring following an injury sustained in pre-season training.
“Having previously suffered with his hamstring it is anticipated that the surgery following this injury will provide a permanent solution to the problem.
“Ryan will not be available for our upcoming pre-season tour but will continue to be closely monitored by our medical team to determine when he can return to training.”
It’s another blow for Sessegnon, who will have been hoping to impress new manager Ange Postecoglou, especially given the incoming competition at left-back of Destiny Udogie.