Liverpool, who had three straight victories in the Champions League group stage and lead the group, would be defeated when Atalanta visited Anfield on Wednesday night.
Before kick-off, the team gathered around the center circle for a minute of silence for Diego Maradona, who died earlier on Wednesday.
Event-poor first half
The first half was an uneventful story and stood for a long time and weighed.
Atalanta had a chance to take the lead, via Robin Gosens, but Liverpool goalkeeper Alisson Becker saved.
Banged in the second half
Just over 15 minutes into the second half, it would explode.
In four minutes, Atalanta had taken over the match and led 2-0.
After 60 minutes, Josip Iličić sent the corner kick right to Alejandro Gómez who headed it sharply past the keeper.
And just four minutes later, the away team would expand again.
Gómez was again behind the goal when he found the ball in the box, which Matteo Pessina nodded on to Robin Gosens, who could put 2-0.
2-0 was also the end result.
Atalanta took a landslide victory and Liverpool suffered their first loss in the Champions League group stage.