Collymore wrote in the People: "Fergie never had to worry about any of those things. He had the trust of every fan and everyone around the club. But now if United lose at the Etihad or Anfield, the manager will be forced to answer some very tough questions about the direction of the team.
"And fans - some of whom are uncertain Moyes is the right man - will to say, 'I told you so', if he fails to quickly position the team above the league's other big clubs.
"Virtually anyone who is aged 30 or under and is attached to United is about to experience something very new if this future plan does not get off to a great start.
"I predict that the calls of 'Moyes out' will be heard all too soon. But how will those closest to him react?
"Ferguson was untouchable at Manchester United. I'm afraid that won't be the case for Moyes."