Roma boss Eusebio Di Francesco said winning their Champions League group was especially "satisfying because nobody believed we could qualify at all."
After Tuesday's 1-0 win over Qarabag on Tuesday, paired with Chelsea's 1-1 draw against Atletico Madrid, Roma are the surprise winners in Group C and will be seeded for the knockout stage.
Chelsea go through as runners-up thanks to Roma's head-to-head points advantage, while Atletico -- who reached at least the semifinals in three of the past four seasons -- head to the Europa League.
"It was a great victory, a difficult one, especially as I have no Champions League experience," Di Francesco told Mediaset Premium.
"It's satisfying because nobody believed we could qualify at all, they assumed we'd be eliminated, but we worked hard, proved ourselves and won the group.
"It all started with the opening 0-0 against Atletico Madrid, when we'd just started and were finding our feet, but we suffered and held out for what proved to be a decisive point."
Diego Perotti's header was the difference in Tuesday's win, and he echoed his coach's thoughts.
"It's a wonderful moment for us,'' Perotti said. "When the draw was made, nobody believed in us, but we worked hard and we deserved this first place.
"It was difficult. They were all behind the ball, it seemed as if they had something to play for. We were patient. These games are more dangerous and we didn't lose our heads, fighting together for the goal. Now we're going to enjoy it."
Roma have never won a major European title, only finishing as runners-up in the 1983-84 European Cup and the 1990-91 UEFA Cup, but Daniele De Rossi said he hopes Tuesday's result can change that pattern.
"It's a result nobody dared hope for when the draw was made," De Rossi told Mediaset Premium. "I am particularly glad, as Roma had some real embarrassments in Europe over the years, so this as cleaned up the image of Roma in Europe in a way."