"At the moment I am finding myself on the outside looking in but I am working hard in training and keeping myself fit," Fletcher told the Manchester Evening News.
"You expect a strong squad at United. We have always had strong squads over the years.
"I have to be because games are coming thick and fast now and with injuries and suspensions you could be called upon anytime and I have to make sure I am 100 per cent ready."
Paul Scholes' return has made the job of breaking through all the more difficult for Fletcher but he was delighted to see the 33-year-old return.
"What a reception for Paul," added Fletcher. "The whole stadium was on it's feet and rightly so. It was an appreciation of a world-class footballer. He is definitely one of the best midfielders in the world and has been consistently so for over 10 years.
"Paul is a pleasure to play with but a nightmare to play against in training. But you want to play against the best even in training and Paul Scholes is definitely the best."