The two teams were clearly full of confidence following their recent good form, and Christos Mandas had to be at his best in the 12th minute to parry Keinan Davis’ low effort before thwarting Hassane Kamara’s follow-up with his legs.
However, Udinese were almost the masters of their own downfall midway through the half, when Mergim Vojvoda underhit a backpass, and Mattia Zaccagni tried to take the ball around Maduka Okoye, only for Lennon Miller to race back and clear the danger.
Miller had come on after just 16 minutes when Jakub Piotrowski had to be withdrawn, and the Friulani suffered another injury blow seven minutes before half-time, as Oumar Solet hobbled off.
Moments later, Kamara tried his luck from range in a bid to become the first Udinese player since 2011 to score in each of the opening three matches of the Serie A campaign, but Mandas made a sprawling save down to his left.
The Lazio goalkeeper was yet to concede in the league this season, but he was powerless to stop Jesper Karlstrom giving Udinese the lead four minutes after half-time, as the Friulani captain latched onto Davis’ layoff and fired just the second Serie A goal of his career through Mandas’ legs.
Kenneth Taylor whipped a shot past the post as the Biancocelesti looked for an immediate response, before Okoye saved Zaccagni’s header at point-blank range during a scramble in the Udinese box.
Jurgen Ekkelenkamp forced Mandas into a save at the other end, but Lazio continued to push, and they levelled 15 minutes from time when Zaccagni crossed low into the box for Davide Frattesi to poke home his third goal in as many Serie A games since his summer arrival on loan from Inter Milan.
It looked like the Biancocelesti would have to settle for a draw when Zaccagni fired a half-volley against the post, but summer signing Gudmundsson popped up two minutes from time to nod home Danilho Doekhi’s cross.
It is Lazio’s fourth victory in their past five away league games, while Udinese see their unbeaten start to the campaign end, and have now won just one of their last seven Serie A home outings (D2, L4).
Flashscore Man of the Match: Mattia Zaccagni (Lazio)