The Big Four in the ATP probably is good for tennis. Novak Djokovic, Rafael Nadal, Roger Federer,Andy Murray … they bring structure and clarity to every tournament they enter, and attention to every draw. "Whom will they face before the semi-finals?"
At times, however, wouldn't a little churn at the top seem like fun? The impulse, then, is to scan the rankings and look for a potential interloper into the tetrarchy.
Jo-Wilfried Tsonga has the game, but can he ever hold his focus? David Ferrer is a bulldog standing on his hind legs but a man has to strike some winners to make the top four, doesn't he?
Tomas Berdych and Mardy Fish are competitive, but their best days seem behind them.
Gilles Simon, Nicolas Almagro, Gael Monfils, Juan Monaco? If the whole of the ATP schedule were on clay, one of them might be able to claw into the first four.
It seems more likely that a player with demonstrated physical prowess would make the leap. John Isner and Milos Raonic, for instance. Both men crush the ball and have big serves. If they can learn a bit of finesse, couldn't they break that glass ceiling?
The player perhaps most likely to push towards the top is Juan Martin del Potro, a big hitter with something extra. He won the US Open in 2009, beating Nadal and Federer, and he might already be up there with them if not for a wrist injury that idled him for a year. And he is still only 23.
Could he do it? Well, probably not. The man who will break up the Big Four might still be a boy.