Moyes has found himself under pressure since replacing Sir Alex Ferguson at the club over the summer, with United stuttering to three defeats in their opening seven Premier League games.
But Saha, who worked under Moyes during his time at Everton, believes that the 50-year-old is the right man for the job, as long as he is given time to put his ideas into practice.
“I have no doubt that Moyes will be a success at Manchester United,” Saha said. “But there is also no doubt that he is fighting against time.
“When you are in his position it comes down to how long it takes to put the team together, find the right tactics and get the best out of them. He is driven by an obsession to develop players.
“He is obsessed with working hard every day, working hard to improve the mentality of his players and every aspect of their game.
“He is a tough manager – including being tough on himself – and that is an asset for any club.”
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