The speed of Roger Clemens's fastball--usually clocked at 95 to 97 miles an hour--has earned him the nickname "Rocket Man." His fastball (which Rickey Henderson of the Oakland Athletics told the Providence Journal "is as difficult to hit as a marble shot out of a cannon"), combined with a sharp breaking curve ball, has established Clemens as the best pitcher in the major leagues. He has won four American League Cy Young Awards (given annually to the league's best pitcher), was named the American League Most Valuable Player (MVP) in 1986, and has won twenty or more games in four different seasons. A fierce competitor, Clemens's temper has often caused him trouble, but his will to win has made him the best.

William Roger Clemens was born August 4, 1962, in Dayton, Ohio. He is the youngest of Bill (a truck driver) and Bess Clemens's five children (he has two brothers and two...