A little more than two months after being thrashed 4-0 at Dinamo Zagreb in its group-stage opener, Atalanta beat the Croatian club 2-0 on Tuesday to keep alive its chances of advancing to the knockout stage.
The Italian side dominated much of the game and easily could have scored more goals, but settled for a penalty from Luis Muriel and a solo effort from Alejandro "Papu" Gomez.
"It's always difficult to explain," Atalanta midfielder Marten de Roon said with a laugh when asked about the difference between both matches. "Today maybe we prepared a bit better. We played the ball well and with depth and they dropped deeper and we had more chances.
"We didn't play in Zagreb. It was a match in which Atalanta wasn't there."
Last-place Atalanta moved to four points in Group C, one behind Dinamo and two behind Shakhtar Donetsk, which it plays in its final group match.
"It's like today, we need to win," De Roon added. "We said before tonight, we need to win both matches to stay in Europe and with a bit of fortune, maybe even in the Champions League."
Manchester City drew 1-1 against Shakhtar to secure first place in the group.
Dinamo hosts City in their final group game.
"We're going to risk everything," Dinamo coach Nenad Bjelica said. "We have nothing to lose, we can only win, just like Atalanta today. Playing like that is easier. A point does nothing for us, we will believe right until the end, we will believe in ourselves."
Atalanta had only won one of its last eight matches in all competitions but it had managed to secure an impressive point against City in its previous Champions League match.
And it could have been 2-0 up after just three minutes as first Hans Hateboer and then Mario Pasalic missed good opportunities.
Atalanta kept up the pressure and took the lead in the 27th minute. Robin Gosens' shot crashed off the crossbar and Muriel was fouled by Dino Peric as he attempted to reach the rebound.
Muriel stroked the resulting penalty into the bottom right corner.
Muriel blasted over the bar in the 32nd and Atalanta went even closer to doubling its lead moments later when Hateboer's effort was cleared off the line by Peric, making up for his penalty foul.
Atalanta was almost made to rue its missed opportunities as Mislav Orsic — who scored a hat trick in Zagreb — curled a shot onto the crossbar.
The Italian side finally got its second goal two minutes into the second half as Gomez cut inside from the right, bamboozled his way past a defender and fired into the far bottom corner.