Premise: Frank Sedgman . In his 1979 autobiography Jack Kramer , the long-time tennis promoter and great player himself , included Sedgman in his list of the 21 greatest players of all time . Sedgman is one of only five tennis players all-time to win a multiple slam set in two disciplines , matching Margaret Court , Roy Emerson , Martina Navratilova and Serena Williams . The Grand Slam tournaments , also called majors , are the four most-important annual tennis events . Ken McGregor . He and his longtime doubles partner , Frank Sedgman , are generally considered one of the greatest men 's doubles teams of all time and won the doubles Grand Slam in 1951 .
Hypothesis: Frank Sedgman played tennis.
Label: ENTAILMENT