Callahan's a pretty solid dude on his skates though. He definitely got hit hard, but he's not Havlat, so he didn't explode on impact.
I read somewhere that someone asked some hockey players (yes that's vague lol but I can't remember the context) what it was like to get hit by Kronner and the response was it's like running into a fire hydrant.
I ran into a fire hydrant on my bike once when I was a kid. It sucked.