Carlos Augusto got the opener when he headed home a corner kick in the 48th minute.
Marcus Thuram scored the second in added time with a potent strike into the roof of the net.
It was the first time these teams have played each other in the top division since 2003 and although Inter had lost only one league game all season, they struggled to impose themselves on 15th-placed Como.
However, the Nerazzurri did enough and the victory took Simone Inzaghi's men within three points of leaders Atalanta (40) and within one of Napoli (38). Inter have a game in hand over both clubs.
Earlier on Monday, Fiorentina missed the chance to go fourth after conceding two second-half goals to lose 2-1 at home to Udinese.
The match was a special one for Edoardo Bove, the Fiorentina player whose collapse with a heart issue led to the suspension of the game with Inter on December 1.
Bove was fitted with a defibrillator implant soon after and sat on La Viola's bench for the first time since his collapse.
Edoardo Bove is all smiles after making his return to the Fiorentina dug out. (AP PHOTO)
He is not allowed to play but his position on the sideline alongside coach Raffaele Palladino was seen as a step towards normality for the 22-year-old midfielder.
The Florence club had won a record eight consecutive league games before losing to Bologna 1-0 on December 15, and looked to be back on track when Moises Kean converted a penalty after just eight minutes.
Kean became the first Fiore player to reach double figures in the league since Federico Chiesa in the 2019-20 season.
However, Udinese were a different prospect after the break.
Lorenzo Lucca equalised with the aid of sloppy defending four minutes into the second half and then Florian Thauvin found space on the edge of the box to curl in the second eight minutes later.
The result left Udinese (23) in ninth place and Fiorentina (31) in fifth.
16°C