Manolo Gabbiadini scored the winner against his former club to lift Bologna off the foot of the table.
This was a relegation tussle, although the Orobici were technically mid-table despite their two-point penalty and feeling the pressure after a shock home defeat to Genoa. Bologna were bottom alongside Pescara and Siena, though the club stood by Coach Stefano Pioli.
Archimede Morleo and Panagiotis Kone sat out bans for the home side, joining the injured Gianluca Curci, Robert Acquafresca, Gyorgy Garics, Henry Gimenez, Carvalho and Cesare Natali. Atalanta missed Davide Biondini, Ferreira Pinto, Daniele Capelli and Guido Marilungo.
Manolo Gabbiadini’s screamer stung the palms of Andrea Consigli, but it was Alessandro Diamanti who broke the deadlock with an absolute missile of a free kick into the near top corner, helped by a deflection off German Denis.
Tomas Manfredini thought he had equalised when nodding in a Luca Cigarini free kick, but it was ruled offside.
Consigli reacted quickly to parry a Sorensen strike, then Gabbiadini acted as a defender to intercept the cross for Federico Peluso.
Ex-Atalanta striker Gabbiadini was unlucky not to get a goal on 34 minutes, as his curler from the edge of the box beat Consigli to thump the upright.
Denis failed to redirect a stunning Giacomo Bonaventura overhead kick, while Diamanti then set up Saphir Taider, who slipped at the crucial moment when clear on goal.
Denis got Atalanta back on level terms at the dawn of the second half. Cigarini’s cross-field pass bounced just in front of El Tanque to hit a half-volley back across Consigli.
Consigli punched away a dangerous Diamanti free kick, but the move continued and Gabbiadini acrobatically volleyed in the loose ball at the near post.
Manuel Pasquato forced a difficult save out of Consigli late on, but Bologna held on for the precious victory.