Tuchel says his men’s team spirit against Diego Simeone’s side was ‘unbelievable’ as goals from Hakim Ziyech and Emerson sent Chelsea to their first quarter-final since 2014.
After winning the first leg 1-0, the Blues needed to avoid defeat against Atletico Madrid in order to progress.
Chelsea took the lead inside 34 minutes thanks to Ziyech after a quick counter from the hosts.
Substitute Emerson settled the Rojiblancos defeat during the dying embers of the game.
"Very good performance, unbelievable effort, even from the guys in the stands... could feel we totally wanted it,” Tuchel told BT Sport after the game.
"They tried to pressure us high in the first half but opened up some spaces in the back of the midfield and we could exploit it.
“Second half there were minutes where we suffered but we were ready to do what was necessary to win.
"We missed Andrea Christensen, Thiago for many weeks - big personalities. I tell Kurt Zouma this morning he plays and he steps up. It's about team work, courage and reliability of feeling safe around each other.
"Is it a penalty? (Azpilicueta foul) Azpi got a bit frightened because his ball was short, I did not see it but was a bit frightened.
"We know if we cannot find solutions with offensive play we can rely on our physical game.
“We were absolutely not afraid to put it on a physical level if we don't get offensive solutions. We enjoyed the battle. The guys were totally on and sharp, we were super hungry to go through.
"Quarter-final means there's only four games - it's a big step and feels excellent."
