The former Chelsea and Tottenham Hotspur manager has taken over Zenit with them sitting second in the table, but said that the players are capable of winning all their remaining league games.
"I was delighted to accept the offer to coach Zenit because the club is as ambitious as I am," BBC Sport quotes Villas-Boas as saying.
"I hope to have a lot of success with the team and my first aim is to win the Russian championship. I am sure we have what it takes to win our remaining matches and become champions."
Villas-Boas watched his new side beat Borussia Dortmund on Wednesday night but still go out of the Champions League on goal difference.