Captain Papu Gomez scored with a superb second-half strike as Atalanta secured a first-ever Champions League victory with a 2-0 home success over Dinamo Zagreb on Tuesday that keeps their knockout round hopes alive.
Luis Muriel also netted at San Siro, where Atalanta are playing their home games while their regular stadium in Bergamo undergoes renovations, as the Italians proved full value for their success.
Manchester City have won Group C with 11 points from five matches, followed by Shakhtar Donetsk on six and Dinamo five. Atalanta sit at the foot with four points but are still very much in contention for second place in the pool.
They travel to Ukraine to meet Shakhtar in their final pool encounter on December 11, while Dinamo host Manchester City on the same night.
Colombian forward Muriel put the hosts ahead from the penalty spot after he was felled in the box by Zagreb defender Dino Peric as the ball crashed back off the crossbar from Robin Gosens's angled shot.
Hans Hateboer saw his shot cleared off the line, but at the other end Dinamo's Mislav Orsic, scorer of a hat-trick against Atalanta on matchday one, curled an effort against the bar.
The home side's endeavour was rewarded on 47 minutes when Gomez picked up the ball 30 yards from goal, beat a defender and flashed a low shot into the far corner of the net.