Who won Tennis Grand Slam twice?

How many tennis players have won every Grand Slam singles title more than once? I assume Roger Federer is one ... asked Nick Baker

Actually, he isn't: although Roger Federer has won 17 Grand Slam singles titles - more than any other man - he's only won the French Open once.

Rod Laver uniquely achieved a calendar-year Grand Slam twice - as an amateur in 1962 and as a professional in 1969. The only other man to win each of the four major singles titles more than once is Roy Emerson, who won twice in France, Wimbledon and the US, to go with six Australian championships.

Five women have won each major title more than once. Margaret Court, who won a record 24 singles titles, won three times at Wimbledon, five times in France and the US, and 11 times at home in Australia. Chris Evert and Martina Navratilova both won all four tournaments at least twice.

But pride of place must go to Steffi Graf - she's the only person to win all four titles at least four times. Steffi's eventual haul of 22 titles included four Australian Opens, six French, seven Wimbledons and five US Opens.

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