The Blaugranas coach was relatively pleased with his side's win, but feels they were not on top of their game, while ruing Gerard Pique's injury
The Catalans grabbed the lead early in the first half via Cristian Tello, but an own goal from Dani Alves and a strike from Romulo put the away side in front.
However, Lionel Messi then came to the rescue for Barcelona as he netted a double to help them to victory in their Group G opener.
"The performance was good, but not the best. We played well, opening up the pitch. The best thing was the reaction of the players," Vilanova stated at a press conference.
"It's a good feeling because it's important to start with a win. They were difficult to unlock and made things hard for us with a couple of counterattacks.
"We had a lot of chances. Teams only employ this kind of approach when they play us."
Vilanova then went on to discuss the fitness of Gerard Pique, who was forced off after 12 minutes of play due to injury, and stressed that Barca will use youth players to replace the centre-back during his absence.
"We will use players from the reserve team [to fill the void created by Gerard Pique's injury]. Hopefully he recovers soon, but, if not, we will use our young players."
Barcelona resume match action on Sunday when they lock horns with Granada.