Zac Efron Falls During Baywatch Shoot

Zac Efron ate it HARD after failing to master the classic "Baywatch" run.

One minute the sculpted heartthrob is hitting strides and the next he's eating sand as The Rock and the rest of his babe-mates looked on. Check out the photos ... the fall might have been scripted, but it doesn't matter. It's funny either way.