Real Madrid and Barcelona
celtic - rangers Celtic Rangers is a huge rivalry I'll admit, but THE biggest rivalry in the world is the Derby Della Capitale, which is AS Roma (Roma) vs. SS Lazio (Lazio)
Argentina vs. Brazil.
soccer world cup......i guess
it is soccer
What is the biggest participant sport in the world?
Soccer is one of the world's biggest sports.
FIFA World CUP
The biggest event in soccer is actually the Fifa World Cup. That is what brings the WHOLE world together. Also, you could count the Euro Cup. Thought hat is not as big as the World Cup.