Born in San Diego, California, she loved horseback riding as a child, but her mother was unable to pay the cost of riding lessons. So, she took up the game of tennis. Her tennis career began at the age of 10 on the municipal courts of San Diego. Her first coach, Wilbur Folsom, encouraged her to switch from a left-handed grip to right and she soon became a baseline specialist with tremendous power, accuracy, and a strong backhand. After Folsom she was coached by Eleanor 'Teach' Tenant who had also previously coached Alice Marble the Wimbledon champion of 1939. At age 14, she won 56 consecutive matches and the following year became the youngest ever to win the U.S. national championship for girls 18 and under.