The Camp Nou outfit went up by a three-goal margin within the opening 20 minutes, but Javier Mascherano's sending off and a debatable penalty awarded to the hosts almost led to them surrendering their advantage.
"I was surprised at Cesc Fabregas' caution over celebrating a goal," said Vilanova to reporters. "You [journalists] have better images to judge his performance though.
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"The penalty broke our rhythm. Before that, I had never seen our team play so well in the first 20 minutes.
"I introduced Xavi [after Mascherano's sending-off] because with ten men, I wanted more control. He was fresh and could ensure that."
Long-serving keeper Victor Valdes' mistakes proved directly responsible for several of the promoted side's goals, but Vilanova says that he will stand by his first-choice custodian.
"Valdes has been giving us so much over so many years that we cannot doubt him at this point."
The 30-year-old has appeared in all of the Primera Division leaders' games so far, conceding 11 goals in eight starts this season.