Martina Hingis (born 30 September 1980) is a Czechoslovak-born Swiss professional tennis player who spent a total of 209 weeks as the singles world No. 1. She has won five Grand Slam singles titles, twelve Grand Slam women's doubles titles, winning a calendar-year doubles Grand Slam in 1998, and five Grand Slam mixed doubles titles; for a combined total of twenty-two major titles. In addition, she has won the season-ending WTA Championships two times in singles and three times in doubles and is an Olympic medalist.
Hingis set a series of "youngest-ever" records during the 1990s, including youngest-ever Grand Slam champion and youngest-ever world No. 1. Before ligament injuries in both ankles forced her to withdraw temporarily from professional tennis in 2002, at the age of 22, she had won 40 singles titles and 36 doubles titles and, according to Forbes, had been the highest-paid female athlete in the world for five consecutive years, 1997 to 2001. After several surgeries and long recuperations, Hingis returned to the WTA tour in 2006, climbing to world No. 6 and winning three singles titles, and also receiving the Laureus World Sports Award for Comeback of the Year. She retired in November 2007, following months of injuries and a positive test for a metabolite of cocaine during the 2007 Wimbledon Championships, which led to a two-year suspension from the sport.
In July 2013, Hingis came out of retirement to play the North American hard-court season, partnering Daniela Hantuchová. After achieving moderate success in 2014 playing with Sabine Lisicki and Flavia Pennetta, she partnered with Sania Mirza in March 2015; together they won three consecutive Grand Slam titles. During her comeback, Hingis also won all four Grand Slam mixed doubles tournaments alongside Leander Paes and a silver medal partnering Timea Bacsinszky at the 2016 Summer Olympics in Rio de Janeiro.
Widely considered an all-time tennis great, Hingis was ranked by Tennis magazine in 2005 as the 8th-greatest female player of the preceding 40 years. She was named one of the "30 Legends of Women's Tennis: Past, Present and Future" by TIME in June 2011. In 2013, Hingis was elected into the International Tennis Hall of Fame, and was appointed two years later the organization's first ever Global Ambassador.