Following Roma’s earlier success against Udinese, victory was the only way for Inter to immediately retake their position at the summit.
The hosts’ blistering start was rewarded within three minutes, as Alessandro Bastoni smothered Gustav Isaksen to win the ball back and offloaded it to Lautaro Martinez, whose exquisite first-time shot kissed the underside of the crossbar on its way into the top corner.
The Nerazzurri didn’t let up from there either, with Martinez heading off-target from Federico Dimarco’s free-kick, before Ange-Yoan Bonny’s cutback was deflected into the side netting.
Lazio finally started to settle and show some intent of their own as the quarter-hour mark came and went, although Mattia Zaccagni fired over while under pressure from Manuel Akanji.
Inter still carried a threat with Petar Sucic volleying narrowly wide from a delightfully dinked Nicolo Barella pass before Akanji sent a first-time strike over the crossbar.
Isaksen then saw an ambitious attempt routinely held by Yann Sommer, while Zaccagni continued to cause problems, with Akanji and Sucic both getting booked for fouling the winger.
In stark contrast to the first half, Inter initially looked flat after the restart, and Denzel Dumfries was booked for a blatant push on Zaccagni before Matteo Guendouzi forced Sommer into a save.
It took just 11 minutes for Cristian Chivu to take action with a double change, and his side responded within six minutes. Barella played the ball out to Martinez and the striker laid it off to Dimarco, who delivered a pinpoint low cross for Bonny to convert and double Inter’s lead.
Shortly after, Piotr Zielinski also beat Ivan Provedel with a wonderful strike, but the goal was ruled out due to a Dimarco handball earlier in the move.
Pedro tried to pull the visitors back into the contest, but he struck marginally wide before Mario Gila’s header from the Spaniard’s free-kick hit the woodwork and came agonisingly close to crossing the line before being gathered by Sommer.
The goalkeeper made one more big stop to deny Luca Pellegrini and ensure Inter were not unduly troubled, as they recorded an 11th win from their last 12 matches across all competitions, while also ending Lazio’s six-game unbeaten run in the process, leaving the Biancocelesti ninth.
Better yet for the Nerazzurri, each of the previous three leaders during the November international break have gone on to lift the Scudetto, though with such fine margins at play, this still promises to be a title fight for the ages.
Flashscore Man of the Match: Nicolo Barella (Inter Milan)