Serena Williams' journey to the top of the women's game

Serena Williams, who is set to retire from the sport after the U.S. Open. The following is a timeline charting her rise to the top of the women's game:

1999: Defeated Martina Hingis in the U.S. Open final, becoming the first African American woman to win a Grand Slam singles title after Althea Gibson in 1958.

2001: Failed to make another major final until 2001, when she lost the U.S. Open title clash to sister Venus.

2002-03: Missed the 2002 Australian Open due to injury and then embarked on an incredible run that included winning five of the next six Slams and losing in the 2003 French Open semis.

2004-07: Career was affected by injury, but she still won Australian Open titles in 2005 and 2007.

2008-09: Won the 2008 U.S. Open to break her Grand Slam drought before claiming the Australian Open and Wimbledon titles the following year.

2010: Won her 12th major at the Australian Open. Missed the U.S. Open over medical complications after cutting her foot on glass while celebrating her Wimbledon win.

2011: Underwent surgery after a life-threatening blood clot was detected on her lung. Made the U.S. Open final but lost to Australia's Sam Stosur.

2012: Won Wimbledon in 2012 and followed that with Olympic gold on the same grasscourts, beating top seed Victoria Azarenka in the semi-finals and third seed Maria Sharapova in final.

Won her fourth U.S. Open title, beating Azarenka in the final.

2013: Won her second Roland Garros crown in 2013, one of 10 titles she lifted that year to reclaim the world's top ranking. Added another U.S. Open title to her collection.

2014: Claimed seven titles, including her sixth U.S. Open, which was her third in succession, to join compatriots Chris Evert and Martina Navratilova on 18 Grand Slam wins.

2015: