Napoli defender Kalidou Koulibaly admits they let themselves down for Sunday's shock defeat to Sassuolo.

Koulibaly concedes they dropped their standards on the day.

“Tonight, we wanted to win but we didn't," he told Sky Sport Italia. “We're sorry for the defeat. If we stop at this defeat, we won't improve.

“We can't use last Thursday's game as an alibi. We need to think about winning this Thursday's game against Rijeka and on Sunday in the League against Bologna, let's think big.

“We created many opportunities to score, but we didn't grab them."