Liverpool face a huge battle to stay in the Europa League after suffering a shock home defeat to Atalanta in the quarter-final first leg at Anfield.

Former West Ham forward Gianluca Scamacca scored in each half, before ex-Chelsea player Mario Pasalic added a late third goal to ensure the Italians start strong favourites to reach the semi-finals when the sides meet in next Thursday's return in Bergamo.

Scamacca broke the deadlock in the 38th minute after Caoimhin Kelleher allowed his low drive to creep under him.

On a deeply frustrating night for below-par Liverpool, Darwin Nunez missed two big chances, while Harvey Elliott's curling attempt struck the bar before dropping on to the post.

Mohamed Salah, who started on the bench, forced a fine save from Juan Musso after Kelleher had atoned for his error to stop the unmarked Teun Koopmeiners from doubling Atalanta's lead.

The Egyptian also had a goal disallowed for offside, but the Reds were flat and lacked urgency in their play - and were punished for some dreadful defending.

Scamacca - who had just one season at West Ham before joining Atalanta last August - took advantage of being left unmarked by doubling the lead with a crisp finish on the hour.

Pasalic's 83rd-minute strike came after Brazilian midfielder Ederson was afforded too much space to shoot and, when Kelleher made a save, the Croatian snapped up the rebound to score.

The winners of this tie will face Benfica or Marseille in the semi-finals, with Benfica establishing a 2-1 first-leg advantage to take to France next week.