The highly-rated 20-year-old has been out of action since October after being diagnosed as having a build-up of patella tendonitis in his left knee.

He had surgery and was targeting a return in time to take part in pre-season training - but now faces another operation.

Orient physio Tony Flynn told the club's website: "Simon's not making the progress that we'd all have liked.

He's going to have another scan and then see a specialist soon - but this is a long-term injury.

"Both Alan Shearer and Ronaldo had the same problem and spent a long time out - and it may be a little longer than we expected before Simon returns."