Real Madrid vs. Barcelona: The El Clásico rivalry transcends football.

Liverpool vs. Manchester United: A historic rivalry with European encounters.

Bayern Munich vs. Borussia Dortmund: The Bundesliga's biggest clash.

AC Milan vs. Inter Milan: The Derby della Madonnina with European stakes.

Chelsea vs. Arsenal: London rivals battling it out on the European stage.

Manchester United's period of success under Sir Alex Ferguson.