Argentine forward Gonzalo Bergessio put Catania in front in the 21st minute of the rainy match in Sicily and Serbia winger Milos Krasic equalized in the 49th — with the help of an error from Catania goalkeeper Mariano Andujar.
Krasic also set up Alessandro Del Piero for a possible winner in the 81st but the 36-year-old Juventus captain missed with a weak header.
Juventus and Udinese have eight points each but Juventus leads on goals scored.
Udinese drew 0-0 at Cagliari, while Atalanta extended its impressive start with a 2-1 win over fellow promoted club Novara.
Atalanta trails the leaders by four points, but the Bergamo squad would be two points clear if not for a six-point penalty from a match-fixing and betting scandal that also resulted in a 3 1/2-year ban for its captain Cristiano Doni.
Matias Schelotto scored with a close-range header for Atalanta in the 34th and Luca Cigarini doubled the lead with a shot from just beyond the area in the 59th. Filippo Porcari pulled one back for Novara in the 88th.
Also, Siena beat 10-man Lecce 3-0 with two goals from Emanuele Calaio and another from Mattia Destro; and Lazio drew 0-0 with Palermo.
Earlier, Chievo Verona beat 10-man Genoa 2-1 with an injury-time winner from Davide Moscardelli.
On Saturday, Inter and AC Milan got their first wins. Inter beat 10-man Bologna 3-1 in coach Claudio Ranieri's debut and injury-plagued Milan edged Cesena 1-0. Also, Napoli and Fiorentina drew 0-0.
In Verona, Moscardelli scored a headed goal in the third minute of added time to follow up his goal in a 1-0 win over Napoli on Wednesday.
Rodrigo Palacio had put Genoa in front in the 48th with his league-leading fourth goal of the season and Sergio Pellissier equalized for Chievo in the 74th.
Pellissier failed to convert a penalty in the 60th after Genoa defender Dario Dainelli was sent off for a hard foul on the striker.
For his goal, Palacio did well to hold off Chievo's defense and beat goalkeeper Stefano Sorrentino after taking a pass from Cristobal Jorquera.
Recently fired Inter coach — and former Genoa manager — Gian Piero Gasperini had wanted to acquire Palacio in the offseason, and the former Boca Juniors striker is showing what made him attractive to Gasperini.
Pellissier equalized with a header following a corner kick from recently acquired United States midfielder Michael Bradley.
Bradley also began the action that led to the winner, sending a long pass up the right flank to Gennaro Sardo, who crossed to Moscardelli.
