In baseball, it often happens that a fly ball is hit where two or more fielders would have a chance to catch it. In that case, the fielders have to agree as to who will make the catch. If they miscommunicate, they might collide and let the ball drop; then the batter reaches base and the fielders reach ESPN's Not Top Ten blooper reel. This is a particular risk because the fielders will normally be watching the ball instead of each other.
Casual players seem to handle this just by yelling "I got it". Do professional teams have a more elaborate system? Sometimes it appears on TV that players are shouting as they go for the ball, but it's hard to tell what they are saying. I would think there should also be some rule for what to do if both players try to call for the ball.
I suppose the same issue must arise in cricket, and I'd also be interested in that answer if it is different.