Manager Jurgen Klopp said Liverpool struggled to “find their mojo” as two early goals from Milan Pavkov gave Red Star Belgrade a shock victory in their Champions League group-stage encounter.
Victory would have taken Liverpool three points clear at the top of Group C but they drop to second following Napoli’s draw with Paris Saint-Germain in Italy.
Forward Pavkov headed his side into the lead after 21 minutes and fired a powerful effort into the bottom corner to make it 2-0 shortly afterwards.
“I saw a few games like this already and it is really difficult to find your mojo,” Klopp said.
“We made life a bit too easy. I don’t say it is already serious if you lose twice but we have to make sure it will not not happen again.
“We had a lot of moments when we could get in control of the game and we didn’t do it, we just made the wrong decision.”
Red Star dominated the first half and came close through Vujadin Savic and El Fardou Ben Nabouhane before Pavkov’s opening goal.
Liverpool’s Daniel Sturridge squandered a great chance from six yards out in the 17th minute.
Klopp’s side had more than 80% of the possession and hit the woodwork twice in the second half but could not score as Red Star recorded their 10th clean sheet in their last 15 home games in Europe.
Liverpool were not at the races in Serbia and they were punished for it.
A hard-fought draw against Arsenal at the weekend appeared to take the stuffing out of Jurgen Klopp’s side as they were slow to react to the hosts’ blistering start.
Sloppy passes in midfield and poor choices in attack were taken advantage of – Pavkov’s second goal arrived after Liverpool had given the ball away.
Klopp was short on midfield options, given the injury to Jordan Henderson. Naby Keita was fit enough only for the bench, while Adam Lallana made just his second start in Europe since 2014.
Liverpool improved in the second half as Salah came close on several occasions but Red Star blocked everything in front of goal.
The Reds were favourites to progress from Group C before kick-off but they are still to play PSG and Napoli in their final two games so last year’s finalists may face a nervous wait to see if they qualify for the knock-out stages.
Red Star Belgrade manager Vladan Milojevic spoke about how important this game was for his side before kick-off and hoped home advantage would play a big role.
Liverpool walked out to a sea of red and white and the fans’ pre-arranged display was an intimidating sight.
The hosts seemed fired up by it – winger Marko Marin was shown a yellow card for protesting in the fifth minute.
Klopp also described Red Star’s line-up as “the most offensive” he had seen from them in Europe this season and attack is exactly what they did.
Marin had the first shot on target – a tame one from close range after 10 minutes – and Red Star enjoyed 56% of the possession before Pavkov gave them the lead.
They could have scored earlier in the half when skipper Savic turned and fired over the bar from a corner, before Ben Nabouhane’s powerful shot was palmed away by Liverpool keeper Alisson.
Red Star had scored only one goal in four and a half hours of Champions League football before they netted twice in half an hour against Liverpool.
It was almost a perfect evening for Red Star – who became the first Serbian team to win a Champions League group-stage game – but Filip Stojkovic was visibly frustrated as he was carted off the field with an injury in the second half.