Vilanova thinks that Barca must stay focused to maintain their strong form after starting La Liga with a 100% record.
He told reporters at a pre-match press conference: "You can also see that nothing is easy. Sometimes we underestimate other teams, but we saw how good Sevilla really were.
"We're always the ones to beat and it's becoming increasingly difficult because other teams know how we play.
"It's an important week because we're playing big teams: Sevilla, Benfica and Madrid, but it's not key. Unless something big happens, titles are always decided later on."
Barca face the sternest test of their credentials under Vilanova this week when they follow up a trip to Lisbon with the resumption of hostilities with Real Madrid on Sunday, October 7.