Sunderland striker Steven Fletcher has surprised medical staff after hitting the training ground this week.
Last season's top scorer, who had surgery on the problem, has started running unhindered and has been doing catch-up double training sessions at the Academy of Light training ground in a bid to get fit.
Fletcher is unlikely to feature in Fulham's visit to the Stadium of Light for the season's opener this weekend.
Sunderland boss Paolo Di Canio said: "There is a big improvement and we are happy with his progress. We are waiting for him."
