OK. I think I got it. E, if he's prepared to go full on dive for the ball and has any chance at all, has to yell "I got it!" If the IF is just drifting out there and knows absolutely he can get it, he will have time to call E off? (I do recall from what little playing I did that camping under a ball for an easy catch, then getting called off by someone trying to make a spectacular diving play was more than mildly irritating.--of course, maybe the adolescent angst of that doesn't apply--or shouldn't apply--to play at this level.)