Jack Kramer, a tennis champion in the 1940s and '50s and a promoter of the sport for more 60 years, died at his home in Los Angeles, his family said. He was 88.
Kramer died late Saturday from a soft tissue cancer that was diagnosed in July, according to his son Bob Kramer.
"We'd hoped he could hang on for a few more months," Bob Kramer said. "At the end, he didn't want to go to the hospital, so the family gathered and he died at home."
Kramer won the Wimbledon men's singles title in 1947 and the men's U.S. Championships, the forerunner of the U.S. Open, in 1946 and '47.
He also won seven other Grand Slam titles in doubles, all at Wimbledon or the U.S. Championships. Kramer was the No. 1 player in the world for much of the late 1940s.
He was among the most successful of the touring pros who played in arenas across the country in the early 1950s.
After his retirement in 1954, due to an arthritic back, Kramer worked as a tireless promoter of the sport. He was among those who led the way for a more unified, open tennis tour.
Kramer was a founder of the Association of Tennis Professionals and served as its first executive director. In 1973, he led ATP's principled boycott of Wimbledon, which helped players gain more control of their own careers from national tennis associations.
Later he served on the Men's International professional Tennis Council, the worldwide governing board.
Since the 1950s, Kramer was heavily involved in the Los Angeles Tennis Open, serving as tournament chair, director and even referee in matches. For three years during the 1980s, the tournament was called the Jack Kramer Open.
In the days before he died, Bob Kramer said his father had been following the U.S. Open in New York.
"He was a big admirer of Roger Federer, who played with a single-handed backhand, like himself, and played a more classic game," Bob Kramer said. "Over the years, he was a big fan of Pete Sampras, and he thought Marit Safin was one of the most-underrated players."
The last tennis match he saw in person was on July 27, when he went to UCLA for the tournament that once bore his name.
Kramer owned more than 100 race horses over the years and made two trips to Del Mar race track this season to watch his horses run.
Kramer's wife, Gloria, died in 2008. Along with Bob, he is survived by four other sons, David, John, Michael and Ron, and by eight grandchildren.
Bob Kramer said details of a memorial service would be announced this week.