Liverpool will have to await confirmation of their place in the knockout stages of the Champions League, after they came from behind to draw with Napoli.
Red Bull Salzburg’s 4-1 win over Genk means Klopp’s men will need to avoid a loss against the Austrian side in their final Group E match to progress.
After a slow start by Liverpool, Dries Mertens gave the away side the lead mid-way through the first half, clinically finishing the first clear-cut chance of the game.
The Reds searched for a leveller first over half an hour, before a towering Dejan Lovren header gave Klopp’s side a deserved goal.
Despite dominating the ball for the vast majority of the match, Liverpool were unable to find a winner, and will feel it was an opportunity missed to make their sixth group stage game a formality.
How it happened
The hosts struggled to break down Napoli’s well-organised back five for the majority of the first half, with the usually formidable trio of Roberto Firmino, Sadio Mane and Mohammed Salah unable to make an impact.
With just a quarter of an hour played, Liverpool’s holding midfielder Fabinho fell awkwardly, and was unable to continue despite momentarily returning to the action.
He was replaced by Georginio Wijnaldum, but Liverpool were still unable to gain a foothold in the game, and five minutes later Mertens pounced to put Napoli ahead.
The Belgian latched onto a long ball, and fired a half-volley into the bottom left from an acute angle.
VAR came into question once again as the goal was checked for a potential offside and a possible foul on Virgil Van Dijk by Mertens.
The goal was awarded, but referee Carlos Del Cerro Grande instructed Liverpool to delay the kick-off, as the stadium announcer revealed the goal would be reviewed again for a possible offside.
Four minutes after the ball hit the net, Liverpool were finally allowed to restart the game, much to the annoyance of the Anfield faithful.
The Premier League leaders grew into the game after going behind, and saw a Van Dijk header saved by Napoli goalkeeper Alex Meret.
As the half drew to a close, the home side pinned the Italian’s into their own half, with Mane and Firmino beginning to produce some slick combination play.
James Milner saw a close-range shot blocked by Meret after some quick feet, before massive penalty appeals were waved away after a tug on Mane.
Despite the pressure, Liverpool went into the break trailing, with the prospect of being leapfrogged by Napoli in the Group E table.
The theme continued early in the second-half – Meret spilled a Jordan Henderson shot but his blushes were saved as Kalidou Koulibaly hacked Firmino’s shout off the line.
As the game reached the hour mark, Meret was called into action once again, gathering a tame Salah effort from 12 yards out after a quick Liverpool counter.
Firmino then nodded a header narrrowly wide, after a teasing Alex Oxlade-Chamberlain cross – the Englishman was introduced for Joe Gomez as Klopp reshuffled his team.
But the equaliser finally came through an unlikely source. Dejan Lovren rose highest to thump home a header from a Milner corner.
The Reds remained well on top following the goal, however chance were at a premium.
Countless crosses were swung into the Napoli box, but the Serie A club’s three centre halves were equal to each one.
Klopp sent van Dijk forward in the closing stages of the game, but he too was unable to provide a solution to the problem posed by Carlo Ancelotti’s side.
Del Cerro Grande’s final whistle brought an end to a frustrating 90 minutes for the home team’s players, and their fans.
Liverpool will now travel to Austria in two weeks time knowing that any slip up could see them dumped out of the competition they won for the sixth time last season.
The Reds’ attention will first turn to Saturday’s visit of Brighton as they look to maintain their unbeaten Premier League record.