Roma coach Rudi Garcia was visibly disappointed after the 2-0 defeat against Napoli in the afternoon.
The Giallorossi were completely dominated by the hosts in the first 45 minutes of the game and failed to restore parity after reacting positively in the second.
And the Frenchman was puzzled as to why his players were dominated in the first half of the game.
"The best team won today," Garcia said during his press conference.
"Winning here is always difficult, to do it you have to play for the full ninety minutes not just for one half.
"We only started to play in the second half, we were lucky to be only a goal down and had chances to equalise.
"For sure is that this is not the right approach to win big games like this one.
"We will analyse the game tomorrow.
"I will speak with the players to understand how they felt.
"I believe it was a mental problem rather than a physical one else it would have been impossible to play such an intensive second half."
Roma also lost big games against Juventus and Bayern Munich this season but the Frenchman is not yet ready to analyse in detail results against top teams in the Serie A and Europe.
"We will see in the future," Garcia said.
"I will not talk about the defeat against Juventus as we've already talked a lot about that one.
"As for today, yes, Napoli were stronger. We have to get back on winning terms in the league [but] we will first focus on the Champions League game.
"[The title race?] The lead is in danger. Not because we lost today but because the league is wide open.
"We have a lot of work to do."
