Five days from that defeat and despite Chelsea winning a League Cup tie on penalties against Fulham in midweek, the 33-year-old Portuguese coach was still angry enough to concentrate on the Old Trafford setback a day before Swansea City visit on Saturday.
Clearly riled by critics who dismissed his team as "naive and stupid" for the way they played at Old Trafford, Villas-Boas said they did not know what they were talking about.
Sunday's defeat was the first league loss for 17 months for the former Porto boss who told Friday's media briefing that Chelsea were superior to United and were only guilty of failing to take their chances.
"I am surprised that people take the view to criticise us for being naive and stupid at Old Trafford," he said.
"What happened at Old Trafford was a negative result for Chelsea but we were the best team and the most efficient team and the team who had the initiative in the game.
"What we did was defend the essence of British football and football well played.
"I find it strange that people related to football don't know where to position themselves regarding what is best for football and what is best for fans, because fans are the most important part of our game.
"It was an entertaining game for the world. Pity we didn't come away with the three points but I think we were superior during the 90 minutes.
"In the end, it's the victory that counts. We missed the victory."
Chelsea went behind after eight minutes at Old Trafford when Chris Smalling headed home unmarked and were 3-0 down by half-time before Fernando Torres pulled one back for the Blues at the start of the second half.
Chelsea might have scored another when Torres was guilty of missing an open goal, but they might have lost by an even heavier margin if Wayne Rooney had not missed a penalty or saw an attempt bounce back off a post in the second half.
Villas-Boas however, said although Chelsea were beaten they were still serious contenders for the title.
"We are five points behind the leaders and we have to try to shorten the distance as we try to progress with a couple of wins," he added.
Chelsea and Swansea have never met in the top flight before and Swansea's only league win at Stamford Bridge came in a Second Division match in the first of their nine visits in 1925.
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