Jurgen Klopp rolled the dice on Liverpool’s Champions League qualification at Anfield and suddenly added a layer of drama and tension to his side’s attempt to progress to the knock-out stages this season.
Two goals in four minutes, from Josip Ilicic and Robin Gosens, inflicted a rare group defeat for the 2019 European champions as Klopp sent out a severely weakened team.
The situation with illness and injuries within the Anfield camp had left their manager talking about “missing instruments out of the orchestra” ahead of the visit of an Italian side they swept aside with contemptuous ease in their first meeting.
Brighton await the defending Premier League champions at lunchtime on Sunday on the south coast and the Liverpool manager had already made clear his dissatisfaction at the fixture scheduling.
But after this defeat, Liverpool’s return to Europe for the home meeting with Ajax next week suddenly takes on added importance as Klopp searches for the victory he needs to be sure of finishing in the top two in this group.
Team selection was a gamble by Klopp, but a calculated one given his crippling injury list and the perfect three-win start his side had made to the Champions League campaign, three victories that had come without conceding a goal.
Logic dictates that teams wait to qualify for the knock-out stage before resting players but Klopp went a game early, with a back four that included three players who have yet to start a Premier League game this season.
It showed, as the Italians, still smarting from the 5-0 humbling Liverpool handed them on their own ground three weeks ago, dominated.
It did not help Klopp’s kids that Mo Salah, starting after his recent layoff because of a Covid positive, gifted the ball to the visitors with a stray pass in his own half and Ilicic shot over from 20 yards.
More gaps appeared in Liverpool’s half after eight minutes when Gosens cut in from the left and almost beat Alisson at his near post, only for the Brazilian to make a strong save in the end.
Youngster Neco Williams was also caught in possession and Alejandro Gomez shot inches wide of Alisson’s left-hand post as the Italians continued to dominate while a poor clearing header from Kostas Tsimikas flew straight to Ilicic who shot over, first-time, from the edge of the area.
It was predictably shaky, with Joel Matip striving manfully to anchor things in the middle of the defence, but as the half wore on Liverpool appeared to have weathered the storm, responding to the increasingly frantic gesturing from their manager on the touchline.
Klopp cut a concerned figure at times but, as long as the game remained goalless, it was far from a disaster and Atalanta’s frustrations grew as their ideas shrank.
Ilicic flung himself to the ground theatrically, after the barest of contact from Tsimikas but while Liverpool lacked some pace and inspiration all over the field - experienced players as well as rookies - they were keeping Atalanta at bay.
In fact, while visiting keeper Pierluigi Gollini was a virtual spectator, the half could have ended with Liverpool ahead as Atalanta failed to deal with a Tsimikas cross and the ball fell to Salah who changed his angles before driving a shot over.
Still, it remained a balancing act for Klopp between keeping the stars he had named to his bench rested and trying to secure the win that would make qualification a mathematical certainty.
Gomez opened the second half with a speculative shot that Alisson scurried over to stop easily and that was enough to have Klopp ordering Fabino, Roberto Firmino, and Diogo Jota - scorer of a hat-trick in Italy three weeks ago - off his bench to warm up.
It was too late. Just before the hour, a spell of patient Atalanta pressure ended with the excellent Gomez curling over a perfect far-post cross which allowed Ilicic to evade Tsimikas and push the ball on the half-volley past Alisson from six yards.
With the news of Ajax leading, the timing of the goal was concerning; certainly concerning enough for Klopp to throw on four substitutes although none had worked up a sweat by the time the visitors doubled their lead after 63 minutes.
Again, Gomez was the architect with a superb far post cross that Hans Hateboer headed back across goal for the unmarked Gosens, having ghosted away from Rhys Williams, to volley in from eight yards.
Alisson 6; N Williams 5, R Williams 5, Matip 6 (Minamino 85), Tsimikas 5 (Robertson 61, 6); Jones 5, Wijnaldum 5 (Fabinho 62, 6), Milner 6; Salah 6 (Firmino 62, 6), Origi 5 (Jota 61, 6), Mane 5.
Adrian, Kelleher, Cain, Clarkson, Koumetio.
Gollini 6; Toloi 7, Romero 7, Djimsiti 6; Hateboer 7, de Roon 7, Pessina 6 (Al Miranchuk 85), Freuler 6, Gosens 8 (Mojica 75, 6); Ilicic 7 (Zapata 70, 6), Gomez 9.
Palomino, Lammers, Muriel, Piccini, Rossi, Ruggeri, Scalvini, Panada, Sportiello.
C del Cerro Grande (Spain) 7