Xiang Liu

The London Games will prove to be an opportunity for redemption for one of China's biggest sports stars. The 2008 Olympics couldn't have been more disappointing for Liu, who carried high expectations and massive popularity in his home country before pulling out of a preliminary heat in the 110-meter hurdles due to an Achilles' injury. The setback prompted a public apology to his compatriots. China's hopes for Liu were hardly misplaced; he won gold in the 110 hurdles in 2004 in Athens, matching the world record before eventually breaking that mark with a time of 12.88 seconds two years later. But he was surpassed in 2008 by current world record holder and archrival Dayron Robles, who won gold in Beijing. With Liu healthy again, the rivalry was reignited at last year's world championships. Robles appeared to win until Liu protested that he was surging to victory when the Cuban interfered with him. Officials agreed, and Robles was disqualified, with Liu given silver behind American Jason Richardson. That medal was Liu's fourth at worlds - one gold, two silvers and one bronze - in addition to four from the 60-meter hurdles at indoor worlds, including a silver from the 2012 event in March. But he'll surely be targeting gold in London in what he has said will be his last Olympics and the culmination of years' worth of drama.