Didn't watch the game but looks like he planted correctly
Just his momentum didn't stop and I guess being sandwhich didn't help
momentum can't just stop, Kawasaki, that's the whole point about momentum
he planted his leg awkwardly and it snapped w/o any contact from an another player, as it seems ... just bad luck on his side, I guess - didn't look like anything a player doesn't do at least 10 times every game, kind of like one of Cisse's injuries while at 'Pool.
anyways, hope he recovers quickly and fully, no player deserves this stuff