The 1-0 win - via Romelu Lukaku's goal - guarantees Roma a sixth place finish.
"It does leave a bitter taste in the mouth to concede a goal like that against 10 men," Gilardino told DAZN.
Advertisement
Advertisement
We should've done better, but the lads played well against a strong team who were fighting for an important objective. We largely reduced Roma to shots from outside the penalty area."
Gilardino also revealed he signed a new deal on Sunday morning.
I had expressed my desire to the club some time ago, which was to provide a sense of consistency to this project. I am happy here, we have laid strong foundations and that is fundamental for a coach.
I signed the contract this morning with the director. I am happy, as is the club, and now we want to build on these foundations with players who are hungry."