After Sunday's agonising 3-2 Premier League loss to United, Arsenal’s title hopes have come under question, especially after Aston Villa and Manchester City picked up three points.
After going ahead through a Lisandro Martinez own goal, strikes from Bryan Mbeumo, Patrick Dorgu, and finally Matheus Cunha sealed the Gunners' defeat, which has closed the gap at the top to just four points.
Rooney spoke after the game and blamed Arteta for the loss after he panicked when the game did not go his way from the start.
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"I think there was a panic," Rooney said.
"I think Arteta is brilliant and I've praised him a lot, but I think he panicked after Man United went 2-1 up and to make four changes at once.
"I think he's panicked and rushed those changes, rather than let Arsenal try and get back into the game with the players they had on the pitch, and it didn't pay off.
"You can see the closer it gets to the end of the season, it's going to be a challenge, a real challenge, Arsenal in my opinion, are still favourites to win the league, but I don't think they're going to have it all their own way."
Arsenal now switch their focus to the Champions League, where they face FC Kairat as the side aim to maintain their place at the top of that league.
After that, they face Leeds United, and a loss could cut their lead to just one point as the title favourites start to slip.
