With the Serie A campaign that is approaching an end, and Inter and Napoli side by side at the top, every match is a must-win for the Milan Club in this phase of the season.
A collision with Roma represented a potential banana skin for the Nerazzurri, but they thought they had started the perfect start when Davide Fratesi put the ball in the net within 10 minutes, only for the flag of the assistant referee to shorten his parties.
Their misery was aggravated halfway through the first half when the Giallorossi took a shock. There was a huge element of Fortuin involved, but the visitors did not mind when a loose ball fell conveniently for Matias Soule in the area and he hit the San Siro silent.
Things may have gotten a lot worse for Inter, just after Roma twice in the vicinity of expanding their lead by Eldor Shomurodov and Bryan Cristante, but neither of them failed to work Yann Sommer in the goal of the hosts.
For an inter -side so desperate for a goal to recalculate their title hoop, their reaction was a bit overwhelming, and they never really came close to finding a level within 20 minutes after the restart. That brought Simone Inzaghi to make a double change, but he must have left his head when his substitutes had little effect.
In reality, the game should have been more than the hosts than Niccolo Pisilli was given the freedom of the San Siro in the area, but he was incredibly wide from 12 meters out.
The chances came thick and fast for Roma, and they wasted another one, just a few minutes later when Artem Dovbyk clearly raced, but his slow footwork enabled Francesco Acerbi to come back and make a goal -saving tackle.
Only one shot on goal in the second half of Inter by the time of the 85th showed how bad they struggled today. It was a crushing blow to Inter's title hop, and they will now watch Napoli later tonight in the hope that they will also slide.
The day was Van Roma, who stimulated their own top-four hope, although their destiny is still out of their own hands.
Flash score Man of the match: Matias Soule (AS Roma)
View all match statistics with flash score.
In the other 15:00 kick-off in Serie A, Fiorentina Empoli defeated 2-1 to stay in the mix for the European places.