How do you dive for the ball?

Everyone tells me it's the rebound button. But my player never dives for a loose ball. Do you have to be a certain athletic or defensive level to be able to do it? I'm already pretty high up on both categories.

I hit steal/shoot

I got it to work by spamming the steal button but it seems like most times, it doesn't work. How close to the ball do you need to be? In MyPark, I've seen giant dudes with long arms dive the length of the court.