A cheeky Aleksandar Kolarov free kick rolled under the wall proved the difference, as Roma won 1-0 in Bergamo and Atalanta hit the post.
The Giallorossi made their debut under new Coach Eusebio Di Francesco, but missed injured Alessandro Florenzi, Emerson and Rick Karsdorp. The Orobici lost Leonardo Spinazzola amid a contract dispute, with Mattia Caldara not fully fit.
The last time Roma beat Atalanta was a 2-1 result here in November 2014, managing just three draws and two defeats, home and away.
Alisson and two defenders missed the Robin Gosens roll across from the left, but so did Andrea Petagna, unable to tap in to an empty net.
Edin Dzeko flashed a shot across the face of goal and Gregoire Defrel hit the side-netting from a tight angle, but Jasmin Kurtic should’ve kept his finish down from a Gomez assist.
Daniele De Rossi was last man to block another Petagna effort, as he was last man in the box, but Roma broke through with a moment of inspiration.
Kolarov took a free kick from just outside the area, but as the wall jumped, he rolled it under their feet and into the near bottom corner, where Etrit Berisha simply couldn’t see it in time.
Alisson got down to smother a Papu Gomez free kick and after the restart Petagna prodded straight at the goalkeeper after the Roma defence had opened up.
Andreas Cornelius made his Serie A debut and an immediate impact, forcing a series of corners, and Josip Ilicic tested Alisson with his first touch.
Bruno Peres went off with a groin injury and Atalanta really should’ve equalised at the 88th minute, Gomez's cross finding Ilicic at the far post, but the ex-Fiorentina man somehow prodded it on to the upright from point-blank range.
Roma clung on under siege in the closing stages, Hateboer making the wrong decision with a diving header on Papu’s chipped pass to the back post, then Kolarov with a decisive block on Ilicic, but came away with the precious three points.