Villas-Boas's side went down 2-0 at the BayArena in a defeat that leaves the Russians third in Group C, two points behind the Bundesliga outfit.
They also sit a point behind second-placed AS Monaco, but the Portuguese claims that his troops can turn it around and has earmarked revenge over the Germans in Russia on November 4.
"The group is developing exactly as we expected," he told the club's official website.
"It is still possible, and in the second leg, we must do everything to come back and continue the struggle for qualification.
"We must pay tribute to Bayer, who attacked more and deprived us of the ball."