Inter restored their lead at the top of Serie A to six points as Milan Skriniar's second-half strike sealed a 1-0 victory over Atalanta.
With Milan and Juventus winning over the weekend, Antonio Conte's side needed three points to keep their title rivals firmly at arm's length.
It was hard work, but the points duly came their way, with centre-back Skriniar arrowing home in the 54th minute.
A rare moment of profligacy from Romelu Lukaku might have cost Inter had Duvan Zapata's subsequent effort been a foot to the right, but other than Luis Muriel's shot from a tight angle, that was the closest Atalanta came to a comeback.
Conte's temper did not take long to reach boiling point – Inter's coach receiving a caution, seemingly for complaining against the award of an Atalanta corner, in the 14th minute.
Cristian Romero almost cheered Conte up moments later when he inadvertently lobbed his own goalkeeper, with Marco Sportiello just recovering to head it over.
Samir Handanovic had to be at his best to prevent Zapata from putting Atalanta ahead before half-time, yet Inter's breakthrough came shortly into the second half, with two unlikely sources combining.
Alessandro Bastoni managed to get to a corner, and though he wanted a penalty, claiming he was pulled down, his fellow defender Skriniar was on hand to lash in.
Lukaku looked set to extend Inter's lead within four minutes, only for Romero to make a superb last-ditch challenge.
Inter's work was nearly undone with 20 minutes remaining, but Zapata dragged a low effort wide from the edge of the area.
Zapata's strike partner Muriel tried his luck shortly after, though Handanovic was again in sharp form to help Inter wrap up a 10th straight home league win.
What does it mean? Inter keep on rolling
It is now seven Serie A wins in a row for Inter, whose home form in the competition is formidable. Indeed, the last time they had a longer winning streak at San Siro was back in May 2011, when they reached 13 consecutive victories.
Atalanta, on the other hand, have had a four-match winning streak of their own brought to an end. Gian Piero Gasperini's side would have moved level on points with third-placed Juve with a win, but for now stay fifth.
Defence the best form of attack
With Lukaku having a rare off night in front of goal – he failed to have a shot – Inter needed inspiration from their backline to clinch the points.
Skriniar's finish was composed and clinical, and the centre-back now has three league goals this term. Inter and Leipzig are the only two sides in Europe's "top five" leagues with three defenders who have scored at least three goals this season, with Achraf Hakimi (six) and Danilo D'Ambrosio (three) among that group for the Nerazzurri.
No luck for Lukaku
Lukaku has not had many poor games in an Inter shirt, though the Belgium powerhouse was not at his sharpest on Monday.
As well as failing to register an attempt, he also did not craft any chances, and lost possession more times than any other player (26). His lack of creativity in particular is surprising, considering he has provided eight Serie A assists this season – a record for him in a single campaign in the "top five" European leagues.
Inter visit Torino on Sunday, while Atalanta have a quick turnaround before facing Spezia on Friday.