Fletcher is determined to force his way into Moyes' side by proving his return to fitness for Warren Joyce's Under-21s as an over-aged player.
"It's always frustrating to watch from the sidelines whether you're winning or losing," he admitted. "I just want to be out there to help and do my best. The aim is to be back in the manager's plans and help on the pitch.
"If I can get back involved and help us on the pitch - we've a great squad, great manager and great staff. Manchester United are always strong. Although we've not started as well as we'd have liked, it was a very tough start, and I still expect us to kick on in the next few weeks.
"[David Moyes] has kept liaising with the doctor, speaking to me regularly, even though he's got an important job working with the first team. He's given me the time I need and has been great support. I couldn't ask for any more.
"[A return is a] question for David Moyes. I'm going to hopefully have a few more Under-21 games and finish 90 minutes before trying to work my way into the squad. If I get a chance, I've got to be ready to take it so I'll work very hard with the Under-21 squad. It's a great staff with Warren Joyce and Nicky Butt so I'll make sure I'm ready when the manager hopefully calls upon me."