The Turkish champions were held to a 1-1 draw in the first leg but secured a famous victory when Umut Bulut’s stoppage time winner put the tie beyond doubt.
After falling behind to an early Roman Neustadter strike, Gala responded with two first-half goals from Hamit Altintop and Burak Yilmaz.
“I kiss all my players on the forehead. We should have scored even more during the first half, they were extraordinary,” Terim told NTVSpor. “That’s an important victory for the country, we are in the last eight in Europe.”
The former Fiorentina and Milan coach added that his players deserved the victory as a result of their efforts across the pitch, particularly in defence.
“Sometimes you play good, sometimes bad. Galatasaray did it by our own effort,” he said. “I wanted all the players to do marking and they’ve proved it, this was the difference.”