Two goals in the final 15 minutes from Chievo 1 win on Sunday.
Rodrigo Palacio put Genoa ahead early in the second half when he held off a defender and beat goalkeeper Stefano Sorrentino with a low shot.
But Genoa was forced to play the final 30 minutes with 10 men as Dario Dainelli was sent off after committing a foul in his own penalty area.
Genoa goalkeeper Sebastien Frey saved the ensuing penalty kick from Sergio Pellissier, but Pellissier atoned for his miss in the 75th minute with a header that found the upper corner of the net.
The match appeared headed for draw, but Davide Moscardelli had other ideas as he popped up in the third minute of stoppage time to head home the winning goal.
Atalanta 2, Novara 1
Bergamo, Italy - Atalanta's bright start to the season continued on Sunday as the club recorded its third win in four games, beating Novara, 2-1.
A six-point deduction at the start of the season for match fixing put Atalanta in a hole, but they have dug themselves out nicely with three wins and a draw from four games.
Matias Schelotto tallied the opener for Atalanta in the 34th minute and Luca Cigarini doubled the advantage just before the hour mark.
Filippo Porcari pulled a goal back in the 88th minute for Novara, but it wasn't enough to grab any points for the visitors.
Cagliari 0, Udinese 0
Cagliari, Italy - Udinese remains unbeaten through four games in Serie A after a 0-0 draw at Cagliari on Sunday.
The home side controlled most of the play and came close to opening the scoring in the 13th minute when Nene's shot was cleared off the goal line by Udinese's Maurizio Domizzi.
It was the best chance of the match for either side and helped Udinese join Juventus at the top of the league with eight points.
Catania 1, Juventus 1
Catania, Italy - Catania earned a third draw in four games on Sunday with a 1-1 deadlock at home against Juventus.
Juve had earned seven points from its first three games but fell behind in the 20th minute to Gonzalo Bergessio's goal.
But the Turin side battled back to equalize early in the second half through Milos Krasic, who scored his first goal of the season in the 48th minute.
Siena 3, Lecce 0
Lecce, Italy - Siena claimed its first victory of the campaign on Sunday as Emanuele Calaio scored two second-half goals to help his side to a 3-0 win over Lecce.
Mattia Destro put the hosts in front after five minutes and Calaio's first goal came early in the second half to double the advantage.
Lecce's Andrea Esposito was sent off in the 62nd minute and Calaio capped the scoring 20 minutes from time for a comfortable three points.
Lazio 0, Palermo 0
Rome, Italy - Lazio failed to capitalize on a number of chances on Sunday and was forced to settle for a 0-0 draw at home with Palermo.
Djibril Cisse had a good chance saved by Palermo goalkeeper Alexandros Tzorvas after nine minutes, while striker headed over the net from close range early in the second half.
But the best chance for either side came one minute from time when Tzorvas failed to hold a shot from Miroslav Klose that presented Cristian Brocchi with a great rebound opportunity that he fired wide.
Roma 1, Parma 0
Parma, Italy - Roma won its first match of the Serie A season, defeating Parma 1-0 on Sunday.
The lone goal came in the 50th minute when Pablo Daniel Osvaldo headed home an assist from Aleandro Rosi, giving Roma all three points.
Through four games this season, Roma has managed five points while Parma has tallied just three.