The Brazilian conceded: "I had three things on my mind. I thought the ball was going to bounce harder and come to my hands, but it didn't and I considered kicking it to Chivu or booting it long, but I did neither and gave it to Zalayeta. I take responsibility."
The keeper made up for it later on when he saved Zalayeta's penalty, but insisted the kick should not have been awarded for his challenge on Walter Gargano.
"That was not a penalty! Thankfully I saved it and after that thought we could charge the team up a bit more, asking my teammates to win it for me. We had some chances, but it went this way."
There can be few doubts Napoli deserved the victory, as Julio Cesar admits he was under constant pressure.
"I performed so many saves tonight I can't even remember them all!" he joked. With Roma now six points adrift, is the Scudetto back in the balance?
"It is a tough moment we are all going through, but we have to keep our heads held high because it is better to be six points in front than six behind.
"I know some say the title race is open again, but with so many champions in our side we still have the advantage.
"The Napoli fans were charging up their side and we happened to have our first defeat here today, but there is nothing more to it."