(CNN) -- Veteran forward Cristiano Doni scored twice in the first-half as improving Atalanta stunned Serie A leaders Inter Milan 3-1 in Bergamo on Sunday.
Top scorer Sergio Floccari celebrates opening the scoring in Atalanta's shock victory over Inter.
The 35-year-old Doni, who was an inspiration for the home side all afternoon, set up the opening goal for Sergio Floccari after 18 minutes.
Doni headed the ball across goal for Floccari, who is being touted as a future Italian international, to turn defender Ivan Cordoba and fire home his 10th goal of the season.
The home side doubled their lead 10 minutes later, although Doni's free-kick took a huge deflection off Zlatan Ibrahimovic's arm in the Inter wall to wrong-foot goalkeeper Julio Cesar.
Remarkably, Atalanta extended their lead still further in the 33rd minute when Doni rose between Cordoba and Nicolas Burdisso seven yards out to head home a Jaime Valdes cross.
Inter coach Jose Mourinho made all three of his substitutions as he attempted to spark a recovery, but it was the home side who nearly scored again when Diego De Ascentis struck a post.
Ibrahimovic finally poked home from a yard out after a scramble in the box to net Inter a consolation goal in injury time.
Juventus, however, failed to take full advantage of Inter's loss as they were held to a 1-1 draw by Lazio in the later match -- cutting the gap to three points. AC Milan's 1-0 win over Fiorentina leaves them six points adrift.
Genoa moved above Napoli into fourth in the table as Bosko Jankovic and Guiseppe Sculli scored in a 2-0 success at lowly Lecce, while Julio Baptista was the hero again as Roma inched closer to the top four with a last-gasp 1-0 win at Torino.
The Brazilian scored a superb bicycle-kick two minutes into injury time that leaves Roma eighth, but just five points behind Genoa.
Napoli lost for the fifth time in a row away from home as two Michele Marcolini penalties earned Chievo a 2-1 victory and took then off the bottom of the table, also ending their five-game losing streak at home.
Meanwhile, Australia midfielder Mark Bresciano scored twice as Palermo boosted their UEFA Cup qualification hopes with a 2-0 victory at Sampdoria.