Just like Best Goal Celebrations, even it still happens on the field, but it is not part of the game officially, Football Fight.
What is in your mind, if I say "dangerous sport" ? Do you think about boxing? racing? or other kinds of extreme sport like snowboarding or climbing?
You aren't wrong, but I think you should consider the most popular sport in the world, Football or Soccer (how the American call it) is one of the dangerous sport too.
What makes football is one of the dangerous sport ?it's just because nowadays it is mixed with some kinds of martial art while they played it, so we call it Football Fight.
Even the stars of this sport like Maradona, Eric Cantona, Adriano, even Zinedine Zidane have involved in this Football Fight for once or even more.
If you watch these videos below you will believe it.
The Dirty Side of Football
Arsenal vs Chelsea
Officially it is football, in fact we have watched, it is more likely the mixed of footbal and martial art, isn't it?