( CNN ) -- South African runner Caster Semenya took second place in her Olympic debut Wednesday , three years after a gender controversy sidelined her career and overshadowed her victory in the world championships . She qualified by finishing behind USA 's Alysia Johnson Montano in the 800-meter heats . Semenya , 21 , was the subject of a gender test by the International Association of Athletics Federations following her 2009 victory in Berlin at the world championships . She has since been cleared to compete . The controversial tests followed her explosion into the international scene when she won the world title at age 18 . She crushed her rivals by streaking away to secure victory in a record 1:55.45 -- a time especially highlighted by her sudden rise from obscurity . Her masculine build , chiseled abs and deep voice fueled rumors about her gender , sparking an international outcry . Outraged South Africans rushed to her defense and accused the world of invading her privacy . Read more : Indian athlete under pressure to prove her gender . The organization 's handling of her case also sparked widespread criticism over accusations that it was unclear what standards the world body was using to determine her gender . `` The questioning of her gender is based on stereotypical view of the physical features and abilities attributable to women . Such stereotypes demonstrate the extent of patriarchy within the world 's sporting community , '' South Africa 's minister of women , Noluthando Sibiya , said at the time . Officials for track and field 's world governing body sidelined her for nearly a year before she was cleared to run against women in 2010 after undergoing gender and drug tests . While the governing body said it had cleared her to run as a woman , it declined to provide medical details on the case , citing confidentiality . Expert : Gender testing 'imperfect ' for female athletes . `` I am thrilled to enter the global athletics arena once again and look forward to competing with all the disputes behind me , '' Semenya said after her clearance . `` Running is everything to me . When I am running , I am happy . '' In addition to the gender scandal , she has suffered a series of setbacks , including withdrawing from the 2010 Commonwealth Games because of a back injury . She finished second in the 800 meters at the worlds in South Korea last year . But all the firestorm was in the past as Semenya -- who is coached by 2000 Sydney Olympics 800m champion Maria Mutola -- carried the South African flag in the opening ceremony in London . The powerhouse runner flashed a bright smile as she entered the grandest athletic stage of all . Opinion : Transsexual athletes treated unfairly .
NEW : Semenya takes second place in the 800-meter qualifying heats . The first woman to break a world record at 800 meters was Ethiopia's Tirunesh Dibaba who ran 1:59.00 on July 31, 2009 in Berlin. Her masculine build , chiseled abs and deep voice fueled rumors about her gender . She has since been cleared to compete and says `` running is everything '' to her .