I believe it just means that if you the ball squirts out because you made contact with the field, it is not a fumble.
If a defender makes contact with a player, as soon as the player hits the ground, he is down. If the ball makes contact with the ground after he has been touched, he is automatically down there. If the ball comes out BECAUSE he hit the ground, it is not a fumble.
But if you hit the ground because you stumbled on your own or dove and the ball comes out before any defensive contact, then the ground can in fact cause a fumble. Ask Eli Manning.
OK, that makes sense. Thanks. The reason I was asking was because, as others posted, I wasn't sure how it worked given Eli's fumble.
Yeah, that's pretty much what he said there. Because nobody touched Eli it was correctly ruled a fumble on the field.