Major professional tennis tournaments before the Open Era

Before the advent of the Open era of tennis competitions in April 1968, only amateurs were allowed to compete in established tournaments, including the four Grand Slams. There was no prize money and players were compensated for travel expenses only. However many top tennis players turned professional to play legally for prize money in the years before the open era. They played in separate professional events, mostly on tours involving head-to-head competition, but also in professional tournaments as the biggest events on the pro tour. Professional tournaments, in particular the professional Majors, usually only had a men's draw.

In addition to the head-to-head tours, there were the annual professional tournaments called Championship tournaments, where the world's top professional male players played. These tournaments held with a certain tradition and longevity.

The oldest of these three Professional Majors, or "Professional Grand Slams", was the U.S. Pro Tennis Championships, played at a variety of different venues and on a variety of different surfaces, between 1927 and 1999. Between 1954 and 1962, the US Pro was played indoors in Cleveland and was called the World Professional Championships. The most prestigious of the three was generally the Wembley Championship. Played between 1934 and 1990, at the Wembley Arena in England, it was unofficially usually considered the world's championship until 1967. The third professional major was the French Pro Championship, played between 1934 and 1968, on the clay-courts of Roland Garros, apart from 1963–1967, when it was played on the indoor wood courts of Stade Coubertin.

The U.S. Pro Tennis Championship, also known as the US Pro, was an annual tournament, later known as MFS Pro Championships. It was first organized by player Vinnie Richards when promoter C. C. Pyle withdrew interest in the project. It was first played on the Notlek courts located at 119th Street and Riverside Drive, Manhattan. The tournament was held at various locations in several states until 1964, when it moved to the Longwood Cricket Club in Chestnut Hill, Massachusetts.

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