Roma's bad week ended on a sour note as Atalanta condemned them to a 2-0 defeat at the Stadio Olimpico.
Rudi Garcia's Giallorossi were thrashed 6-1 by Barcelona in the Champions League, and while the French coach was given a vote of confidence heading into this Serie A game, the performance and result may inspire a rethink.
Alejandro Gomez scored and won the penalty which German Denis converted. Maicon saw red for fouling the former while Atalanta's Guglielmo Stendardo and Alberto Grassi followed him down the tunnel before the full-time whistle.
Roma needed to respond quickly to Tuesday's humbling in Spain and looked keen to do so for most of the first half, with Miralem Pjanic and Edin Dzeko going close to scoring.
It would be Atalanta who took a lead into the break, though. Lucas Digne's mistake allowed Gomez to steal the ball and bend it around Morgan De Sanctis from the D.
Pjanic's header was cleared off the line by Luca Cigarini when play resumed and Atalanta almost scored their second on the hour mark, Maxi Moralez unlucky to miss from a one-on-one with De Sanctis.
They would double up in the 81st minute, thanks to Maicon, who conceded a penalty and picked up a red card when fouling Gomez.
Denis coolly converted the spot-kick and Roma were left staring at a first home defeat of the season.
The late dismissals of defender Stendardo and midfielder Grassi for accrued yellow cards might have allowed the Giallorossi back in, but they had nothing left.