At Stanford, Ride renewed her acquaintance with Molly Tyson, who was a year younger than her. The two had met on the tennis circuit as junior tennis players. Although Ride was rated number one at Stanford and Tyson was number six, the two played doubles together. Ride later quit the Stanford tennis team in protest against the university's refusal to join the Pac-8 Conference in women's tennis. To earn money Ride and her then-girlfriend Tyson gave tennis lessons, and in 1971 and 1972 they were counselors at Dennis Van der Meer 's TennisAmerica summer camp at Lake Tahoe, Nevada. In August 1972, Ride played in a doubles match with Van der Meer against Billie Jean King, the world number 1 ranked female tennis player, and Dick Peters, the camp director; Martin Luther King III and Dexter King served as ball boys. Billie Jean King became a mentor and a friend. Ride watched her win the Battle of the Sexes match against Bobby Riggs in 1973. Tyson ended their relationship in 1975, and Ride moved in with Bill Colson, a fellow graduate physics student who was recently divorced.