Roma boss Rudi Garcia said Feyenoord's equaliser was offside but blamed himself for letting a lead slip in Thursday's 1-1 Europa League draw.
Garcia's men took the lead in the first half through Gervinho but were pegged back by Colin Kazim-Richards after the break.
Roma keeper Lukasz Skorupski managed to deflect a point-blank header but the ball rebounded off the crossbar and fell into the path of Kazim-Richards, who made no mistake from close range.
Replays showed Kazim-Richards may have been ahead of the last Roma defender.
"We went too deep, did not press efficiently, although we still had chances to score other goals with Gervinho and [Seydou] Doumbia," Garcia told Mediaset.
"The goal was offside. Now we have to score in Rotterdam. The team needs to gain confidence and take more risks going forward.
Roma have not won a game at home in 90 minutes since November, but Garcia remained confident.
"We won't give up. It's a shame we conceded that goal, but at this moment we are lacking results," Garcia said.
"It's pointless making comparisons with last season. We are doing everything possible to get back to winning ways at the Olimpico, but at the moment hard work isn't paying off.
"We need to be more explosive, take risks more with our mentality than our legs."