| By Steven Kaplan

Less than 10 percent of all tennis shots are hit from a center position on the court. Note that every serve is hit from a slightly off-center start, and each return of serve is hit from even closer to the sideline. Why is it then that more than 90 percent of all tennis balls are fed by instructors from the center?

We are always praising the virtues of "mixing it up" to our students. Perhaps we should take our own advice when it comes to the speed, spin, trajectory and angle of delivering ball feeds.