A victory in Serbia would have consolidated Liverpool's spot at the top of the group but the defeat leaves them in a vulnerable position with games against PSG and Napoli to come.
I think it's one of those periods we need to get through.
James Milner, meanwhile, said in his post-match interview that things went wrong "from the first whistle".
A fee of £2.9 million had been agreed between the clubs but at the eleventh hour, Markovic had a change of heart and made a decision to return to Liverpool, where he is now in the final year of his contract.
Two weeks later, Red Star - playing in front of a loud and passionate home crowd - kept Liverpool's fearsome attacking unit quiet and, in Pavkov, had their own star striker.
Napoli and Paris Saint-Germain's draw in the group's other game means that Liverpool are now level with the Partenopei on six points, one ahead of the French champions.More news: United thriving as underdogs ahead of derby clash: Herrera
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Owen added: "Chelsea are in Europa League action in Belarus on Thursday, but they have coped admirably with their Thursday-Sunday routine so far this season and they have the strength in depth to keep the points from what promises to be an entertaining clash".
Jos3 (@Joe_kop) in his reaction after the game said that: "Lallana is pure garbage".
"Last season everyone was used to us scoring four or five goals", Robertson told British media.
Richarlison, 21, has been ever present in Everton's starting XI since completing a £35million move from Watford in the summer and only Eden Hazard, Sergio Aguero and Pierre-Emerick Aubameyang have scored more league goals than the forward (6) this season.
Yes, Liverpool had the vast majority of possession and territory in the second half of the game, but in truth they rarely threatened bar a half chance here and there.
"You don't forget about these results quickly", Robertson said.