The result was another setback for Solskjaer, whose side are sitting 15th in the table after losing three of their opening six League games this season and are yet to win at home domestically.
United’s meek defeat was also in stark contrast to their 5-0 Champions League rout of RB Leipzig in the previous match, and former club captain Keane offered a withering assessment of the character of Solskjaer’s squad.
Working as a Sky Sports pundit for the game, Keane said he did not “see guys you want to be in the trenches with, guys you trust”.
When those comments were put to Solskjaer, the United boss said: “Well, in the first half there were no tackles, no fighting, you have got to create atmosphere yourself.
“These games against Arsenal were always fierce, tackles flying.
“We didn’t have the tempo or intensity for that, absolutely, and I was disappointed with the first-half performance.
“In the second half we were better. Unfortunately, they got the penalty and we just couldn’t produce the response.”