National Tennis League

National Tennis Leagues (NTL) was a tour for professional male tennis players established in 1967 by George MacCall. In 1970 it was sold to the World Championship Tennis (WCT), a competing professional tennis league run by Lamar Hunt.

The National Tennis League (NTL) was formed by former U.S. Davis Cup captain George MacCall in 1967, as a governing body to a US Professional tennis tour. It was key in moving tennis from a mostly amateur sport to a professional sport.

In 1968 Billie Jean King became the first woman of the Open Era to sign a pro contract to tour, in a group with Rosie Casals, Françoise Dürr and Ann Haydon-Jones as the women's section of the National Tennis League. "On April 1, 1968, we signed with the National Tennis League, as George MacCall's troupe was called. Frankie (Durr) and Rosie (Casals) received a guarantee of $20,000 per annum for two years, mine (Ann Haydon-Jones) was $25,000 and Billie Jean King's was $40,000. George envisaged us playing a lot of matches and tournaments amongst ourselves and did not expect us to be as much involved in open tennis as later proved to be the case....We joined the six men that he already controlled - Emerson, Laver, Gimeno, Gonzales, Rosewall and Stolle. A group of ten was an attractive proposition to offer and he believed he was going to do very well from it. His main problem was one of administration. He had to keep flying all over the world to tie up arrangements with the various associations but didn't leave sufficient time to organize his professional tours in America, the most important part of the operation, and didn't seem to be able or willing to delegate."—From A Game to Love by Ann Jones. Published 1971 by Stanley Paul & Co Ltd; p. 135 and 136

George MacCall served as U.S. Davis Cup Captain from 1965 to 1967. During that time, he organized a professional tennis circuit, the National Tennis League, including Arthur Ashe, Rod Laver, Roy Emerson and Stan Smith.

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