Simone Pepe was the other scorer for Serie A leaders Juventus who stayed unbeaten this season after 15 games and went two points clear of titleholders AC Milan and Udinese.
Giampiero Pinzi finished off a slick counter-attack in the 74th minute to give Udinese, who began the season hoping to avoid relegation, a draw in an entertaining match.
Antonio Floro Flores had opened the scoring for Udinese in the 28th minute before Lazio replied either side of half-time through Senad Lulic and an own goal from Damiano Ferronetti who deflected Miroslav Klose's shot into the net.
Andrea Ranocchia's second-half goal gave Claudio Ranieri's Inter their fifth win in six league games, 1-0 at Cesena, although they were somewhat lucky as the Sea Horses had most of the play and chances.
Parma scored twice in the last five minutes to draw 3-3 with Lecce, Genoa beat Bologna 2-1 and Catania overcame Palermo 2-0 in Sunday afternoon's other games.
"This is the cherry on the cake," the Italy international told Juve's website. "It hasn't been easy in the last months but I've always felt I had the backing of the coach and the team."
Alessandro Del Piero was given a rare start this season for Juventus who needed only four minutes to break the deadlock and Pepe turned in Paolo De Ceglie's low cross at the far post.
