Manchester United legend Roy Keane is unsure whether the team's defence is good enough to win titles.
The Red Devils stumbled to a 0-0 draw at home against Manchester City.
While United started the game brightly, the second half saw City with most of the ball.
Both teams settled for a point, but Keane is not impressed with the quality shown by the likes of De Gea, Harry Maguire, Victor Lindelof, Luke Shaw and Aaron Wan-Bissaka.
He told Sky Sports: "We talk about trust in football, the back four and the goalkeeper are for me still the biggest problems [for Manchester United].
"Okay, they did well today but that's not a back-four that will take you places and that's a big concern.
"You just don't know what you're going to get from Man United right now. That's not a good sign when you're not sure what you're going to get from the team.
"Can you really trust this group to go on a run? The answer is no."
