Maybe a tone in the umpire's ear if the ball is out of the zone (or a tone if it's in and a buzzer noise if it's not). Then the ump can decide if he thinks it caught a part of the zone or something.
But no reviews. I like the review system we have now - although it takes WAY to long - but more reviews would interrupt the pace of play too much.
The players are the human element in the game.
I don't want a complete shift to it. I'm still a fan of the dreaded "human element". I would like to see a tennis system, perhaps where a manager can challenge five (or some other arbitrary number) ball/strike calls per game.
Poll
