The draw means that Atletico are the slight favourites ahead of the second leg at the Vicente Calderon next week, but Tiago has hailed Barcelona as a team with "great quality".
"We worked hard," he told Tele Deporte.
"Barcelona have great quality, but we believe we played a great game. We're all really excited now to go back to the Calderon and give our all."
Atletico return to La Liga action at home to Villarreal this weekend.