United have already come under fire for some below-par displays so far this season, putting fresh pressure on the shoulders of the Dutch boss.
But the former Arsenal midfielder told BetMGM that it was time for the players to look at themselves rather than scapegoat who was in charge.
Petit said: “It’s so hard for a club when they keep changing managers as much as Manchester United have and I actually look at the players there and think they are hiding behind him.
“I don’t like it. These are players with real pedigree and they hide behind him instead of fronting up and doing a job for the team.
“It’s such a pity to see the club in the state it’s in. The Premier League needs Manchester United back at its best and it starts with the players.
“Yes, the manager is responsible for a lot of things and so are the board for getting it right in the transfer market, but at the end of the day it’s the responsibility of the players on the pitch and they haven’t been good enough for some time now.”
United are back in Premier League action this weekend when they visit Crystal Palace.
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