Roma coach Luciano Spalletti was stunned by their Champions League elimination by Porto.
Daniele De Rossi and Emerson Palmieri were sent off in a 3-0 home defeat.
“What happened is we lost a very important match that will change the season going forward and we are going to have to deal with that," the Coach told Mediaset Premium.
“We didn't control the ball well, which was what I had been planning and why I made certain choices. We didn't manage it, just as we were re-organising ourselves after the goal, we went down to 10 and it all became more difficult.
“The three red cards were naïve, because finishing the games with 11 men was our characteristic last season. We never gave the referee the chance to send us off. Now it's happening a lot and I can't understand why, as we could've been a lot calmer."
Going back, what would Spalletti change when preparing for this game?
“I wouldn't change anything, other than the way tonight's game started. We didn't start well, misplaced too many passes and they took advantage of our errors. Above all there were psychological issues, as we felt tense and couldn't get a grip on the game.
“We did have the chances to equalise, even with nine against 11, until those two late goals finished the tie off.
“There will be a period of time that is going to be very difficult. People will try to poke the finger of blame, we must cover our ears, eyes and even noses.
“We've got to get the blinkers on and focus on incredible effort, concentration and sharing of values."