I played Hockey as a kid, for 10 years.
The only real offensive skill you learn is flinging yourself against a person like a brick.
It doesn't translate well outside of the rink.
I guess you learn to hit people with a stick while the referee isn't looking, as well.
Mainly you learn to be aggressive in general, and you keep in shape, but you don't really learn "combat tricks".
The glove is already shaped like a fist, so you just bump your hand against them with no technique when a brawl starts.
I used to keep my stick next to my bed though.
The equipment, stick, helmet, gloves, protections and all is very tough though, it's basically armor. A hockey player without those though is just a brick of meat somewhat accustomed to pain, ready to scream and bump into you, at worst.
With a kevlar helmet on though it's easy to headbutt someone's scalp open even if you're a tennis player.