The champions fell to an own goal from a deflected late Juan Mata strike and the disappointment of a first goalless home game in three-and-a-half years was compounded by Rafael’s dismissal for kicking David Luiz soon after.
Rafael Benitez’s Champions League-chasing side had shaded an encounter that produced plenty of chances at both ends, if not the intensity Sir Alex desired.
"There was no edge to our game but I think Chelsea were the better team," Sir Alex admitted to MUTV. "Training was fine this week and there was a nice edge to it, but today it was missing.
"[Being champions] has a lot to do with it. It’s been a long season for the players and their final really big effort was last week against Arsenal.
"Chelsea's goal was a bit lucky as it deflected off Phil Jones, but it was so late in the game that there was not a lot we could do about it."
Referee Howard Webb brandished United’s first red card of the league season with a minute left when Rafael lashed out following a clash with Luiz deep in Chelsea’s half.
Sir Alex insisted the Blues defender was as much to blame for the incident.
"The referee was bought by the fact Luiz rolled about," the Reds boss said. "He actually elbowed Rafael twice but you know what happens when a player retaliates: he’s always punished more.
"Luiz made it look worse. I don’t think the referee saw it, actually, and he was convinced by