Well, maybe not always, he added. But, then, that's another problem. Outfielders know instinctively that if they move enough to give a fly ball's trajectory the illusion of being straight then they eventually will come in contact. But this instinct doesn't determine exactly when this contact will take place. It also explains why ballplayers have more difficulty catching balls hit directly at them.
Players prefer to step to one side to get a look at the curving path of the ball's trajectory.
This gives a more precise view of the flight path than trying to judge the ball's speed, the researchers said. Science, which published the study, is the journal of the American Association for the Advancement of Science.