Drawing on her tactical instinct and unmatched finesse, Martina Hingis championed an elegant style of play that has slowly been replaced by power — and a whole lot of grunting. Born in present-day Slovakia, she clutched her first racket at the age of 2 and entered her first tournament at the age of 4. (Her mother, a top tennis player in the former Czechoslovakia, named her after Czech tennis legend Martina Navratilova and moved young Hingis to Switzerland after a divorce.) In 1997, at 16 years and 3 months, she became the youngest Grand Slam singles champion of the 20th century and, three months later, the youngest No. 1 ever. A series of ligament injuries sidelined her at age 22. She staged a brief comeback during 2006 and 2007, rising to No. 6 in the world, but retired after testing positive for cocaine (she denies ever taking the drug). Now 30, she married Thibault Hutin, a French equestrian show jumper, in December 2010.