Jurgen Klopp conceded Liverpool's 4-1 humbling at the hands of Napoli in the Champions League was their worst game since he took charge in 2015.

Liverpool were comprehensively beaten by the Serie A side in their opening game in Group A, the heaviest defeat by a Premier League side in their first game of a Champions League campaign since Arsenal lost 3-0 to Inter in 2003-04.

Speaking at a press conference ahead of their second group game at home to Ajax, Klopp did not hold back in his assessment of the "horror show" at the Stadio Diego Armando Maradona.

After Premier League games were postponed following the death of Her Majesty Queen Elizabeth II, Klopp also said his team would rather have played this weekend but "respected" the decision not to.

"Yes, we would have wanted to play," he said. "But for the reasons we all know it didn't happen and, of course, we respect that.

"Now we try to use the time for analysis and training, which made absolute sense after the game we played at Napoli.

"I have lots of thoughts [on the Napoli game]. I watched the game back plenty of times and it was a real horror show, to be honest.

"It was the worst game we played since I'm here. We've had a few bad games, I know that. Everyone remembers Aston Villa [7-2 loss in 2020-21] and some others where we were just not up to speed, but there were always glimpses in these games. In this particular game, [there was] nothing.

"You have to understand why that happens, it's not a common thing, that's more an individual thing. Eight out of 11 [players] were absolutely below their level, three others were not on top level, just [played] a normal game.

"In football it's like this, you sort all individual problems as a team, and that's the first thing we have to do, to follow a common idea again.

"Everything we did since I'm here and everything teams do in football is based on really solid, if not perfect, defending. That's what we had to work on, and that's what we did."

Liverpool have made an uninspiring start to the season, drawing three and losing one of their six Premier League games so far, and Klopp revealed there have been some home truths within the camp following the performance in Naples.

"I know that the players want to sort the situation, we are not over the moon about our season so far," he added. 

"In the end we all agreed that we could have conceded more goals in [the Napoli] game. We could have scored one or two more as well, but we could have conceded more, which is really crazy.

"We had absolute truth - didn't hide anything, we didn't hold back anything, there was no need for that... but not to knock the players down, just to make sure where we are now after this game, this is the starting point for us and now we have to make sure we sort the problems together on the pitch." 

Klopp confirmed that midfield duo Naby Keita and Alex Oxlade-Chamberlain – who were both left out of the Champions League squad – will not return from their respective injuries until October, despite the former being called up to the Guinea squad for the upcoming international break.

"No, I don't expect [Keita] to go on international duty," he said. "The return date is sometime in October, that's why we had to make the decision, with Ox it's the same, and that's why the two boys are not in the Champions League squad."

The Reds boss will also be without Andrew Robertson for the clash with Ajax, confirming the Scotland captain suffered an injury near the end of the Napoli defeat.

"Robbo is not 100 per cent," he said. "Very late, 93rd minute, he actually felt it the next day only, but he's out. I would say at least until after the international break."