Pierre-Emerick Aubameyang’s second-half penalty, conceded through a Paul Pogba foul on Hector Bellerin, proved decisive as United slumped to a fourth consecutive home game without a league win.
Keane criticised United for failing to “roll their sleeves up” and questioned their character, adding: “I don’t see it out there. I don’t see men out there. I don’t see guys I want to be in the trenches with, guys you trust.”
Solskjaer was measured in his analysis of the performance but, when Keane’s comments were put to him, the United manager said he had been disappointed by his side’s tempo and urgency in the goalless opening 45 minutes.
“Well, in the first half there were no tackles, no fighting. In football now you have got to create atmosphere yourself,” he said.
“These games against Arsenal were always fierce, tackles flying. We didn’t have the tempo or intensity today I think, absolutely, and I was disappointed for the first half performance.
“In the second half I thought we were better. Unfortunately they got the penalty and we just couldn’t produce the response.”
Keane was particularly critical of United’s play off-the-ball and questioned whether Solskjaer can rely on his players to perform.
“In management, you have to trust the players because your job relies on the pitch. You’re going to trust those players out there? God help us,” he said.
“Part of football is what you do out of possession. United are not aggressive enough, they aren’t hungry. We saw that against Crystal Palace, Tottenham and again today.
“[Sir Alex] Ferguson always made the point that you need courage to play for Man United. Wanting the ball when you don’t want it. Bravery wasn’t nailing somebody, it was more that side.
“We saw United players tonight taking the easy option. They have to do better. Jamie [Redknapp] said they had the ball for two minutes before the penalty, get in somebody’s face. Smash somebody.”
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