Association of Tennis Professionals

Excerpted from Open: An Autobiography, by Andre Agassi. © 2009 ALA Publishing LLC. Published by arrangement with Alfred A. Knopf, an imprint of The Knopf Doubleday Publishing Group, a division of Random House Inc.

Without any second thoughts, I would say that Jack Kramer was the single most significant figure in the history of his game, tennis.

The image of tennis has long been that of a rather dainty exercise, played before ladies and gentlemen on lawns -- not anything so de classe as "fields." It was the last major sport where amateurs, not those grubby...