Barcelona will need to be at their very best in this season's UEFA Champions League after being drawn in the tournament's 'group of death' while reigning champions Liverpool face a rematch with Napoli.
Barcelona will do battle with Borussa Dortmund, Inter Milan and Slavia Prague in Group F, in what is arguably this season's strongest group.
Madrid and PSG will also meet Club Brugge and Galatasaray in Group A, with the action set to get underway on September 17 and 18, while the final will be played in Istanbul on May 30.
Liverpool's attempt to defend their title will see Jurgen Klopp's Reds come up against Napoli, Salzburg and Genk in Group E.
Meanwhile, beaten finalists Tottenham are in Group B with Bundesliga champions Bayern Munich, as well as Greek giants Olympiacos and the Red Star Belgrade side of Australian defender Milos Degenek.
Perhaps the most open is Group G, where Russian champions Zenit are in with Benfica, Lyon and RB Leipzig.
Juventus take on Atletico Madrid in a repeat of last season's quarter-final in Group D, where Bayer Leverkusen and Lokomotiv Moscow were also placed.
Manchester City, among the favourites for the tournament, take on familiar foes in the form of Shakhtar Donetsk, along with Dinamo Zagreb and tournament debutants Atalanta in Group C.
Europa League winners Chelsea meet last term's semi-finalists Ajax in Group H, with those sides meeting in European competition for the first time. Valencia and Lille complete that section.
Champions League group stage draw in full:
Group A: Paris Saint-Germain, Real Madrid, Club Brugge, Galatasaray
Group B: Bayern Munich, Tottenham, Olympiacos, Red Star Belgrade
Group C: Manchester City, Shakhtar Donetsk, Dinamo, Atalanta
Group D: Juventus, Atletico Madrid, Bayer Leverkusen, Lokomotiv Moscow
Group E: Liverpool, Napoli, Salzburg, Genk
Group F: Barcelona, Borussia Dortmund, Inter, Slavia Prague
Group G: Zenit, Benfica, Lyon, RB Leipzig
Group H: Chelsea, Ajax, Valencia, Lille