<Tr> <Td> </Td> <Td> 2012 London </Td> <Td> Doubles </Td> </Tr> <Tr> <Td_colspan="2"> Last updated on: July 12, 2018 . </Td> </Tr> <P> Serena Jameka Williams (born September 26, 1981) is an American professional tennis player . The Women's Tennis Association (WTA) ranked her world No. 1 in singles on eight separate occasions between 2002 and 2017 . She reached the No. 1 ranking for the first time on July 8, 2002 . On her sixth occasion, she held the ranking for 186 consecutive weeks, tying the record set by Steffi Graf for the most consecutive weeks as No. 1 by a female tennis player . In total, she has been No. 1 for 319 weeks, which ranks third in the "Open Era" among female players behind Steffi Graf and Martina Navratilova . Some commentators, players and sports writers regard Williams as the greatest female tennis player of all time . </P> <P> Williams holds the most Grand Slam titles in singles, doubles, and mixed doubles combined among active players . Her 39 major titles puts her joint - third on the all - time list and second in the Open Era: 23 in singles, 14 in women's doubles, and two in mixed doubles . She is the most recent female player to have held all four Grand Slam singles titles simultaneously (2002--03 and 2014--15) and the third player to achieve this record twice after Rod Laver and Steffi Graf . She is also the most recent player to have won a Grand Slam title on each surface (hard, clay and grass) in one calendar year . She is also, together with her sister Venus, the most recent player to have held all four Grand Slam women's doubles titles simultaneously (2009--10). </P>

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