Danny Mills believes Manchester United could be waiting for up to 10 years to win the Premier League again after their latest failing.
The current champions of England succumbed to a 3-0 defeat to arch-rivals Liverpool on Sunday at Old Trafford and lie 18 points behind leaders Chelsea. It was a record-equalling ninth loss of the season for Manchester United in the Premier League.
"It could be 10 years at least before they win the title again," Mills told BBC's Match of the Day 3.
"The whole rebuilding process is going to take three or four years at least.
"Then you have got to think Manchester City, Chelsea, Liverpool will strengthen - and Tottenham and Arsenal could possibly strengthen as well."
Manchester United romped to the title last season finishing 11-points ahead of nearest rivals Manchester City. But that was under the guidance of Sir Alex Ferguson and the team is now struggling to recreate that winning formula under David Moyes.
They now look almost certain to miss out on a Champions League qualifying place, lying 12 points away from the top four. It would be the first time Manchester United have ever missed out on the Champions League in its current format and the first time in Premier League history since 1993-94.
The Red Devils could still qualify for the Champions League by winning it but must first overturn a 2-0 deficit to Olympiakos when they entertain the Greek champions on Wednesday.
Mills, who played over 50 times for Manchester City before retiring with a knee injury in 2008, says Moyes' lack of experience at the top level is hampering Manchester United.
"David Moyes has not won the league. He has not won a trophy," added Mills.
"If he had a good team he might get back in the top four and Champions League, but I think that they are a long way off competing and winning the title.
"Going into Manchester United, you had to build on massive success and that is where David Moyes has found it difficult."
Mills added to his controversial comments by suggesting Robin van Persie clearly wants to leave Old Trafford.
Van Persie recently committed his future to the Red Devils, but Mills suggests the Dutchman's body language tells a different tale.
"Van Persie doesn't look like he wants to be there and wants to leave," said Mills."You look at his body language and he doesn't look happy there does he? Something is not right with him."