The 27-year-old suffered ruptured ligaments against Arsenal on May 4 and Everton had hoped putting the knee in a brace would solve the problem, however he remained uncomfortable when running.
Everton are hopeful he will be available to manager David Moyes for the league opener against Blackburn on August 16, and club physio Mick Rathbone told evertonTV: "Hopefully he will be there or thereabouts for the start of the season. It´s touch and go."
Copyright (c) PA Sport 2008, All Rights Reserved.
Do YOU want to write for GiveMeSport? Get started today by signing-up and submitting an article HERE: http://gms.to/writeforgms