Grand Prix tennis tournaments

The Grand Prix tennis circuit was a professional tennis tour for male players that existed from 1970 to 1989. It was the more prominent of two predecessors to the current tour for male players, the ATP Tour, the other being World Championship Tennis (WCT).

Prior to the Open Era popular professional tennis players were contracted to a Professional Promoter. Players such as Suzanne Lenglen and Vincent Richards were contracted to these promoters while amateur players followed their national (and international) federation. Later professional promoters, such as Bill Tilden and Jack Kramer, often convinced leading amateurs such as Pancho Gonzales and Rod Laver to join their tours with promises of good prize money, but these successes led to financial difficulties when players were paid too much and falling attendances resulted in reduced takings. In the late-1950s the professional tour began to fall apart. It only survived when the U.S. Pro Tennis Championships, having been unable to give prize money to its winner in 1962, received prize money from the First National Bank of Boston for the following year's tournament. At the same time the concept of "shamateurism" – amateur promoters paying players under the table to ensure they remained amateurs – had become apparent to Herman David, the chairman of The Wimbledon Championships at that time.

In 1967, David announced that a professional tournament would be held at Wimbledon after the Championships that year. The tournament was televised by the BBC and succeeded in gaining public support for professional tennis. In late 1967, the best of the remaining amateur players turned professional, paving the way for the first open tournament. Some professionals were independent at this time, such as Lew Hoad, Luis Ayala and Owen Davidson, but most of the best players came under contract to one of two professional tours:

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