The Old Lady had a 1-0 leading but mistakes allowed Napoli to turn it around and made the final result 1-2.
“It is a tough time, we cannot hide that. Unfortunately we are coming off negative results and feel bitter about losing a game we thought that we were in a great position to win,” said the defender.
“After taking the lead paradoxically we froze up and made two stupid errors. We had lost our identity for those decisive five or 10 minutes.
“We cannot afford that kind of slip-up at the moment and have to be on alert the whole time.
“We can’t cry over spilt milk now and must focus on working together to get back on track against Real Madrid on Tuesday and turning around this negative trend.”