Lazio coach Maurizio Sarri was stunned by their collapse at Napoli on Sunday.
Piotr Zielinski opened the scoring before Dries Mertens twice struck. Fabian Ruiz completed the scoring late on as Napoli won 4-0.
“The team had made steps forward and, as is often the case, every four or five games we have a performance like this. The defects were even more obvious because Napoli put in an extraordinary performance and in my view is the best team in Serie A at the moment," Sarri told DAZN.
“It certainly wasn't the right approach, because we didn't help our case with the first two goals in the opening 10 minutes, and it was even more difficult from there. If we only press half-way, which we did for almost the entire game, against a team of great passers, naturally it's going to go like this. We always started the press late and not as a team. We kept doing it individually and late.
“I see a team that struggles to always be focused. Playing every three days is difficult, but it is not acceptable to go from 10 to 1 in terms of intensity from one game to the next. We kept reacting on the reception of the ball, not the transmission of it, so we were always late."
He added: “We need to understand what these ups and downs are coming from and try to fix them. It's not easy. I expected everything other than this type of performance tonight. The problem is that the team just deactivates sometimes."