Napoli coach Maurizio Sarri was frustrated after defeat to Juventus.
The result was decided at the 88th minute by a sudden Simone Zaza snapshot.
“The game was blocked by a tactical balance between the two sides and it was decided by an unlucky incident right at the end," Sarri told Mediaset Premium and Sky Sport Italia.
“It's a pity to lose in these circumstances after an even match. I don't think there will be big repercussions on the side, but even an undeserved defeat can cause problems psychologically.
“We showed good character, though we could've been more sprightly in attack, but the hard work we did to deny Juventus chances inevitably slowed our usual attacking verve.
“We still created two or three chances and it looked as if the match was going to a draw. Juve's substitution a few minutes before the goal even moved them to 4-5-1 and made it look as if they were happy with a point.
“I think the fact we played on a par with Juventus on their own turf, one of the best teams in Europe let alone Italy, shows Napoli have improved.
“I saw the performance of a strong side. I would've been happier to lose on a counter because we were trying to win at all costs rather than on a deflected shot.
“I think we allowed Zaza too much space and should've closed him down so the shot came from further away. It seemed like an innocuous shot for Reina until the deflection. Unfortunately these things happen and they can be decisive for a match too.
“We had some uncertainty right to the end, as we didn't know if Juventus were going to play three at the back or four.
“We didn't have the pace that we had in other games, but let's not forget Juve's defensive strength has been evident for four or five years now and they concede one every three matches, so it was never going to be easy to break them down."