Milan salvaged a last-gasp 2-2 draw with an equaliser in stoppage time against Champions League holders Barcelona at the Camp Nou.
Arsenal conceded a late equaliser as they were pegged back to a 1-1 draw at Borussia Dortmund in their opening Champions League group game.
Chelsea opened their Champions League Group E account with a 2-0 win against a determined Bayer Leverkusen side at Stamford Bridge.
Valencia endured a frustrating opening night in the Champions League after dominating but failing to score in a 0-0 draw at Genk.
Lucho Gonzalez scored early in the second half to hand Marseille a 1-0 Champions League victory over Olympiacos in Piraeus.
Porto came from a goal down to beat nine-man Shakhtar Donetsk 2-1 in Group G of the Champions League at the Estadio do Dragao.
Viktoria Plzen’s first proper Champions League match ended in a 1-1 draw at home to fellow Group I underdogs BATE Borisov.
Ailton scored the winner as APOEL Nicosia came from behind to beat Zenit St. Petersburg 2-1 in the Champions League.