[deadly738]

Yep this is how I think it is. You have to hold R1 well before you get tackled to allow the "cover up" animation to play out in order for it to work. If the animation does not play out it won't be effective.
When I scramble with Joe Flacco he fumbles almost all the time when he gets hit. But when I use R1 & let the "cover the ball" animation play out, he almost never fumbles now.