AC Milan marked their return to the Champions League after a seven-year hiatus with a 3-2 epic defeat to Liverpool at Anfield.
This will be their first game in the UEFA Champions League since March 2014, when they were eliminated by Atlético de Madrid over two legs in the Round of last 16.
Liverpool and AC Milan have only met on two previous occasions in European competition, with both of them coming in the final of the UEFA Champions League. The Reds won 3-2 on penalties in 2005, before losing 1-2 in normal time in 2007.
Stefano Pioli's men flew to England without the iconic Zlatan Ibrahimovic due to an Achilles injury while Olivier Giroud is named in the squad after recovering from coronavirus.
Jurgen Klopp's men took the lead nine minutes into the game after an own goal from former Chelsea defender, Fikayo Tomori.
Mohammed Salah missed the chance to hand the hosts a two-goal lead after his spot-kick was saved by the visitors who fought back to take a 2-1 lead into the break.
Ante Rebic and Brahim Diaz turned the game around with two goals in two minutes to leave the Anfield faithful stunned.
Klopp's men were saved by the flag seconds into the second half after Simon Kjaer had a goal ruled out for offside.
However, Salah made amends for his penalty miss by scoring Liverpool's equaliser minutes later.
Captain Jordan Henderson sealed the win for The Reds with a brilliant half-volley from the edge of the box in the 68th minute.
Liverpool top Group B ahead of Atletico Madrid who played a goalless draw against 10-men FC Porto at the Estadio Wanda Metropolitano while Milan sit rock bottom.