Career Highlights: The youngest American boxer to qualify for the Games since Davey Lee Armstrong in 1972, Shields, 17, is a two-time junior Olympic champion who has quickly risen through the amateur ranks. She was named outstanding boxer at the U.S. Olympic trials in February, twice beating two-time light heavyweight national champion Tika Hemingway. Shields was just as impressive two months later in her senior international debut at the continental championships. She dominated 2010 light heavyweight world champion Roseli Feitosa of Brazil, winning by a 29-11 margin, and recorded a 27-14 upset victory over three-time world champ Mary Spencer in her native Canada. Things didn't go as smoothly at the world championships in May with an Olympic berth at stake. She easily won her opening bout but lost her next fight to Savannah Marshall in a close decision. However, England's Marshall went on to win the world title, and, by Marshall simply reaching the final, Shields qualified for London. The 2011 national Police Athletic League champion has trained at the same Flint, Mich., gym where former heavyweight champ Chris Byrd got his start. Shields began boxing in 2006 after hearing her father - a former amateur boxer - speak about Laila Ali, who followed in her father's footsteps and began a rise to fame in the ring.