Maurizio Sarri refused to criticise his players after Napoli's Serie A title bid appeared to dissipate with a 3-0 defeat at Fiorentina.
Napoli, coming into the game four points behind Juventus, were blown away by Giovanni Simeone, who drew an early red card from Kalidou Koulibaly and then scored a hat-trick.
The Partenopei had no response but, with his team having recovered similar situations so many times before, Sarri insisted their effort could not be questioned.
"It was a bad performance that we will analyse thoroughly and try to redeem immediately," he said. "But these players have given everything, they must be thanked. It was just an off day.
"It was not at all due to a lack of effort. We got lost after a difficult start to the match, lost our tactical approach and, at 1-0, we became nervous.
"We tried to react, but we failed as a team. We have always been good at reacting this season, not today. But who knows how we would have done at 1-0 if this was 11 versus 11."
Meanwhile, Simeone believes he will have delighted father and Atletico Madrid coach Diego with his first career hat-trick, boosting Fiorentina's Europa League bid.
"We believed we could reach Europe when we won six in a row and believed after losing two," he told Sky Sport Italia. "A great end to the season awaits us."
"It was not easy for Napoli when they went down to 10 men, as we always try to play with the ball - especially against 10 men. My father will be very happy with the hat-trick."