Longest span of Grand Slam singles titles by a tennis player (open era)
Serena Williams
17 years 139 days year(s):day(s)
Australia (Melbourne)

Serena Williams (USA) won the first of her Grand Slam singles titles at the US Open, Flushing Meadows, New York, on 11 September 1999. Seventeen years 139 days later, she collected her 23rd and most recent title, on 28 January 2017 at the Australian Open in Melbourne.

Chris Evert (French Open 1974 to French Open 1986), Martina Navratilova (Wimbledon 1978 to Wimbledon 1990) and Steffi Graf (French Open 1987 to French Open 1999) all achieved 12-year Grand Slam-winning spans in the open era (1968–present). Before then, American Helen Wills Moody won her 19th and final Grand Slam crown 14 years 318 days after her first (US Open, 18 August 1923, to Wimbledon, 2 July 1938). Wills Moody never played at the Australian Open.

The longest span by a male tennis player in the open era is 13 years 207 days, between Roger Federer's (Switzerland) wins at Wimbledon on 6 July 2003 and the Australian Open on 29 January 2017. Australia's Ken Rosewall won his home Grand Slam in 1953 and the last of his eight titles in Australia in 1972 – 19 years later. He was 37 years old at the time of his final Slam triumph.

At the start of the 2017 Australian Open, Serena Williams was tied with Steffi Graf (Germany) for the most Grand Slam singles titles won in the open era (since 1968) – 22. By winning the Australian Open, Serena is now on her own as the most decorated singles player in the open era (male or female), and is just one tournament victory away from equalling the all-time record set by Margaret Court (Australia), who won 24 Grand Slam titles in 1960–73.

Serena won the US Open in 1999, 2002, 2008 and 2012–14; the French Open in 2002, 2013 and 2015; Wimbledon in 2002–03, 2009–10, 2012 and 2015–16; and the Australian Open in 2003, 2005, 2007, 2009–10, 2015 and 2017. She is the only player (male or female) to win at least six singles titles at three of the four Slams, and the only player to claim seven titles at two of tennis' four major tournaments. She is also the only player to win at least 10 Slams in two different decades, and her tally of seven titles in Australia cannot be matched in the open era (male or female). Margaret Court won her home Slam 11 times (1960–73), but only four of them came in the open era (1969–71 and 1973), i.e., when professional players were allowed to compete in tournaments alongside amateurs.

Serena, seeded 2, beat older sister Venus Williams, 6–4, 6–4, in the Australian Open final to regain the world number one ranking from Angelique Kerber, thus making her the oldest female player to hold the No.1 spot.