Gasperini’s men were too hot to handle by leaders AC Milan as the Serie A title race was blown wide open.
Cristian Romero put the visitors ahead inside the opening 26 minutes before Josep Ilicic doubled their lead eight minutes after the break from the penalty spot.
Colombia international Duvan Zapata scored during the dying embers of the game to settle the Rossoneri’s second defeat of the league season.
Speaking to the media after the game, Gasperini insisted his men did well and admits that was their best performance so far.
“Ilicic had a great game, although there were some situations where he is capable of doing better. Everyone had a great game,” the Italian coach told Sky Sport Italia.
“This is one of our best performances since I’ve been here. We achieved it against the Serie A leaders, the Winter Champions, but we were superior in every way and that is immensely satisfying.
“After the game with Liverpool, which was horrible conceding five goals at home, we learned and made the changes we needed to.
“We press the opponents much more, which allows us to protect the defence, and we’ve been doing that for several weeks now.”
Atalanta will be looking to replicate similar form when they entertain rivals Lazio next weekend in Serie A.