Serena Williams competes in men's singles and doubles.
Serena Williams . Her record of 39 Grand Slam titles puts her third on the all-time list and second in the open era : 23 in singles , 14 in women 's doubles , and 2 in mixed doubles . She is the only tennis player in history ( man or woman ) to have won singles titles at least six times in three of the four Grand Slam tournaments , and the only player ever to have won two of the four Grand Slams seven times each ( seven Wimbledon titles and seven Australian Open titles ) . Serena has also won four Olympic gold medals , one in women 's singles and three in women 's doubles -- an all-time record shared with her sister , Venus .