Jose Mourinho congratulated Inter and accepted Roma were deservedly beaten by a "much stronger" side as he suffered a humbling 3-0 defeat against his former team.
Roma were three goals down inside 39 minutes at Stadio Olimpico and failed to muster any sort of response as they slipped to their seventh defeat in 16 Serie A games – their most at this stage since 2008-09.
The defeat was Mourinho's second in eight home league matches as Roma boss, having previously gone 38 without losing at home in Serie A as Inter head coach.
Saturday's contest was the Portuguese's first league meeting with Inter since guiding them to a famous treble in 2009-10 in the second of two successful campaigns at the club.
Roma were without a number of players due to suspension, coronavirus and injuries, with key attacking pair Lorenzo Pellegrini and Tammy Abraham among those absent.
Mourinho had no complaints about the scoreline, with his side registering just one shot on target despite Inter backing off in the second half.
"Inter are stronger than us in normal conditions. In non-normal conditions, they are much stronger than us," he told DAZN.
"Last season, they were 29 points ahead of Roma. Today, with COVID, injuries and suspended players, it was very, very difficult.
"Our attacking potential was practically nil. It was very important to score a goal, because we would only have two or three chances. We had three and didn't score.
"When you play with a defence that has Ibanez and various others in positions that are not their usual ones, you still cannot concede the first and third goals. You just can't.
"Congratulations to Inter. I wish them good luck for their next match."
Hakan Calhanoglu scored directly from a corner to give Inter the lead – the sixth player to do so in Serie A since 2011-12 – before teeing up ex-Roma striker Edin Dzeko.
Denzel Dumfries added a third for Inter before half-time with his first league goal for the club and that is how it remained in a one-sided affair in the Italian capital.
Inter have scored in each of their last 18 away league matches to equal a club record set in 1951 and have won four games in a row in the league, keeping three clean sheets.
The victory would have been particularly sweet for Inter boss Simone Inzaghi, who spent more than two decades playing and coaching Roma's city rivals Lazio.
"Naturally, returning to the Olimpico is not normal for me, as it was my home for 22 years," he told DAZN.
"But I was fully focused on the game as we needed this result. Despite their problems, Roma still had a very competitive first XI.
"I don't know if it was our best performance, but we faced a Roma side that had lost at home only once, so to come here and win like this really boosts our self-esteem.
"It's a great signal and I think the many fans who came to Rome for the game will go home happy."