Roma were dumped out of the Champions League 3-0 on aggregate after Carlos Tevez's winner last night, but Spalletti insisted: "At the start Manchester United created two or three good chances, but then we came out and had the better attacking moves, regardless of the penalty.
On Daniel de Rossi's missed penalty, Spalletti also said: "The game would have changed completely if that had gone in, but when you take certainly responsibilities upon yourself it can happen for it to go wrong occasionally.
"He had scored a very important goal against Genoa on Saturday and made a mistake tonight. It's a shame, as in such crucial matches errors are highlighted even more."
He continued: "United are truly a very strong side, but I have nothing to reproach my squad for.
"We played the game we wanted and created chances. In fact, I expected to have fewer opportunities and possession than we did, but we didn't make the most of them.
"Early on we had problems and Alexander Doni did well to rescue us when we gave away chances with some silly mistakes, but after that we had the better of the play.
"The whole match would have changed with that penalty. Totally different both for my team and Manchester United, so anything could have happened. That goal would have meant a great deal."
Nonetheless, Spalletti is hopeful his team can learn from a second consecutive quarter-final exit to Manchester United.
"We are certainly stronger for this very important experience. I think the team has grown and we must always improve the ratio of goals to chances created, as I didn't see United create much more than we did over the two legs.
"It is true we were unable to score in 180 minutes. In the first leg especially there was very little difference between the teams. We created the moves and did not finish them off."
