Four-time major champion and former world No. 1 in singles and doubles Kim Clijsters won the 2009 U.S. Open title in just her third tournament back from retirement.
The exceptionally athletic Belgian, renowned for her speed, sliding splits and flexibility, defeated Venus Williams in the fourth round, Serena Williams in the semifinals and Caroline Wozniacki in the final en route to becoming the first wild card in the history of women’s tennis to win a Grand Slam title, and the first mother to claim a major since Evonne Goolagong won Wimbledon in 1980.
She successfully defended her U.S. Open title in 2010 — her third U.S. Open crown — and captured her fourth major title at the 2011 Australian Open.
The daughter of a former gymnast (her mother) and a former pro soccer player (her father), Clijsters won her first tour title in 1999. She broke into the Top 5 in 2001.
In her fifth career major final, at the 2005 U.S. Open, Clijsters defeated Mary Pierce for her first Grand Slam title.
But Clijsters struggled with a wrist injury the next season, and in May 2007 she abruptly retired from tennis. In February 2008, Clijsters gave birth to daughter Jada, her first child with husband Brian Lynch, an American and former pro basketball player.
Clijsters’ father Leo died of lung cancer in early 2009. In March of that year, Clijsters announced she would be coming out of retirement later that summer. She returned to the tour in early August; a month later, she had won a second U.S. Open title. Clijsters opened the 2011 season on a 24-3 run, including a win over Li Na in the Australian Open final, and reclaimed the top spot in the rankings for one week on Feb. 14 to become the first mother to ever hold the No. 1 ranking. Shoulder, wrist and ankle injuries limited her to three events over the last seven months of the season; a strained abdominal prevented her from playing the U.S. Open.
TIME magazine named her one of the "30 Legends of Women's Tennis: Past, Present and Future" in its June, 2011 issue.