The group stage of this season's Champions League campaign has been decided following the draw in Monaco this afternoon.
The toughest group arguably belongs to Scottish champions Celtic, who will have to take on Barcelona, AC Milan and Ajax in order to reach the knockout rounds of the competition.
Manchester City have been drawn against reigning champions Bayern Munich, but this season has been kinder to them as they will also face CSKA Moscow and Viktoria Plzen.
Arsenal have a clashes against last season's finalists Borussia Dortmund, while Manchester United and Chelsea will feel that they have simpler routes to the knockout phase with Bayer Leverkusen and Basel placed in their respective groups.
Champions League groups in full:
Group A: Manchester United, Shakhtar Donetsk, Bayer Leverkusen, Real Sociedad
Group B: Real Madrid, Juventus, Galatasaray, FC Copenhagen
Group C: Benfica, Paris Saint-Germain, Olympiakos, Anderlecht
Group D: Bayern Munich, CSKA Moscow, Manchester City, Viktoria Plzen
Group E: Chelsea, Schalke, Basel, Steaua Bucharest
Group F: Arsenal, Marseille, Borussia Dortmund, Napoli
Group G: Porto, Atletico Madrid, Zenit St Petersburg, Austria Vienna
Group H: Barcelona, AC Milan, Ajax, Celtic