The Reds were looking to secure successive Champions League victories this season after Liverpool FC eased to a 3-2 win over Ligue 1 side Paris Saint-Germain at Anfield last month.
Liverpool FC struggled to get going in Italy despite Klopp fielding a strong starting line up despite the looming prospect of a clash against leaders Manchester City at Anfield.
The Merseyside outfit got off to a slow start and Napoli had the best chances to break the deadlock as Alisson Becker looked to be on the brink of keeping a clean sheet.
Liverpool FC looked to be heading for a point against Carlo Ancelotti’s side before Lorenzo Insigne netted a dramatic winner on the stroke of full-time at the Stadio San Paolo.
The Reds are in second place in their Champions League group behind Napoli but ahead of Paris Saint-Germain with back-to-back games against Red Star Belgade next on the agenda.
Klopp admitted that the Reds were disappointing in the Champions League in Naples.
“Sometimes Bobby [Firmino] ran too long with the ball, or Sadio [Mane] ran too long,” Klopp told BT Sport.
“When that happens, you cannot produce. The midfielders or the full-backs tried to go forward, but we lost the ball and had to go back in the other direction.
“It was intense, but we caused the intensity of the game ourselves.
“It was an interesting looking group before we started and it’s still interesting now. We want to play better than we did tonight, but even if we don’t play brilliantly, we want a result. Tonight we weren’t as good as we could be.”
Liverpool FC are unbeaten in the Premier League following an impressive start to the season under Klopp to prompt talk of a title challenge in the current campaign.
The Reds have beaten West Ham United, Crystal Palace, Brighton, Leicester City and Tottenham Hotspur and Southampton in the Premier League this season.
Chelsea FC held the Merseyside outfit to a 1-1 draw at Stamford Bridge last weekend after Eden Hazard netted a brilliant opener before Daniel Sturridge scored a late equaliser.
Liverpool FC will welcome Manchester City to Anfield in their next Premier League fixture on Sunday evening in search of an immediate return to winning ways.
The Reds lost 5-0 to Manchester City at The Etihad back in August 2017 before Klopp’s side were 4-3 winners against Pep Guardiola’s men at Anfield earlier this year.
The Merseyside outfit eased to a 3-0 victory over Manchester City in the first leg of their Champions League quarter-final before Liverpool FC eased to a 2-1 win against the Citizens in the second leg.
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