Atalanta came from behind to record their first away win against Fiorentina in 27 years and move clear in fourth place with a 2-1 victory in Serie A on Saturday.
A superbly struck half-volley from Federico Chiesa gave the hosts a half time lead at the Stadio Artemio Franchi.
But Gian Piero Gasperini's side levelled early in the second half through a Duvan Zapata tap-in before substitute Ruslan Malinovski drilled in the winner from outside the box with 18 minutes remaining.
The result ended an 18-match winless run for Atalanta in Serie A trips to Florence, stretching back to January 1993, and saw them move on to 42 points in fourth, three ahead of fifth-placed AS Roma, who lost 3-2 at home to Bologna on Friday.
Fiorentina have now lost three games in a row and occupy 14th place in the table with 25 points.