Isaiah Thomas proves he can dunk with windmill slam in practice

Isaiah Thomas does in fact have bounce.

The Boston Celtics point guard, who's listed rather generously at 5-foot-9, shared a video Saturday of him in a gym getting way up and throwing down a windmill dunk.

IT has yet to complete a dunk in the NBA in his six seasons, most recently botching an alley-oop to himself in the All-Star Game. He did recover, though, by drilling a wide-open three.