I'm not for a second claiming that soccer is as violent as hockey. Just that there's there's much more endurance and hardship than it looks.
And we haven't even scratched the most violent of them all - waterpolo

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One of the most violent things ever. For some reason half my class played waterpolo in high school. These guys were next level. Not to be messed with outside of the pool neither. Only time I've seen Bud Spencer type slaps - someone getting slapped and seemingly first get horizontal in the air, then fall.