Kenneth Bruce McGregor (2 June 1929 – 1 December 2007) was a tennis player from Australia who won the Men's Singles title at the Australian Championships (now known as the Australian Open) in 1952. He and his longtime doubles partner, Frank Sedgman, are generally considered one of the greatest men's doubles teams of all time. In 1951 and 1952, they won seven consecutive Grand Slam doubles titles – a feat that has never been matched. McGregor was also a member of three Australian Davis Cup winning teams in 1950–1952. At the end of 1952, Jack Kramer induced both Sedgman and McGregor to turn professional. He was ranked as high as World No. 3 in 1952.
McGregor was a fine all-round athlete, excelling in cricket, Australian rules football, and tennis. At 6 ft 3 in (1.91 m), he had a powerful serve and overhead. The great tennis player Ellsworth Vines said of McGregor: "He was the same height as Pancho Gonzales, faster, moved as well and could jump higher, and once he got to the net he was difficult to pass because of his prehensile reach. The handsome Aussie had the most extraordinary overhead of all time." In his 1979 autobiography Jack Kramer, the long-time tennis promoter and great player himself, who brought McGregor into professional tennis, wrote that "McGregor was one of the weakest players but one of the nicest guys who ever played for me in the pros. As nearly as I could tell, all he wanted to do was save up some money, go back Down Under and play Australian-rules football, which in fact, he played better than he did tennis. And that's what he did."
In his 1952–1953 tour against Pancho Segura, McGregor was beaten by 71 matches to 25. In a subsequent 1953–1954 tour against Pancho Gonzales, he was beaten 15 matches to 0.
Ken McGregor is the son of Bruce and Winnifred McGregor. Bruce was the winner of the 1926 and 1927 SANFLMagarey Medal's and was the West Adelaide Football Club's premiership captain-coach in 1927 as well as the Glenelg Football Club's inaugural premiership coach in 1934. Ken has one sister (Betty) who was born in 1927, the day their father Bruce was awarded his 2nd Magarey Medal.
McGregor had a history of heart problems, but was diagnosed with stomach cancer ten days prior to his death on 1 December 2007. He was survived by his wife, two children, and five grandchildren.