Jurgen Klopp’s men came into the encounter knowing a win will secure their qualification to the knockout stages of the competition with the Italian side only needing a point to progress.
Mohamed Salah scored the solitary goal that handed the English side a 1-0 victory over Carlo Ancelotti's men as the Stadio San Paolo outfit were denied a place in the next round of the competition and thus settled for the Europa League.
“It was an important game, we knew they had to win," Koulibaly told Calciomercato
“Maybe, unconsciously, we feared Liverpool because we know they are very strong and that it’s not easy to play against them.
“We could avoid that goal and we should have done more to score one. It went differently, now we will do our best in the Europa League.
“We have a strong team that can beat everyone, and we came close to scoring. A draw was enough, but we lost. It’s just a negative night, we’ll have other positive nights for sure.”
The Senegal international who has been impressive for the Italian side this season has featured in 21 appearances across all competitions, helping them to keep eight clean sheets across all competitions.
The defender will hope to help his side return to winning ways when they take on Cagliari in their next league game on Sunday.