Mark McGwire may eventually be known as the man who saved baseball. His 1998 fight for the single season home run record with Chicago Cubs outfielder Sammy Sosa recaptured the hearts of a generation of fans lost during the 1994 labor dispute. The record 70 home runs put McGwire's name in the record books ahead of greats like Roger Maris and Babe Ruth. But it was McGwire the person, more than McGwire the power hitter, that returned baseball to the public consciousness. In the words of the New York Times editorial on the final day of the 1998 season, "the sight of this gentle, earnest giant handling the pressure of the home run chase with grace and humility has made an entire nation feel better about itself."

It's no surprise that Mark McGwire became a professional athlete. Born in 1963, he spent much of his youth with his four...