Country: United States
Sport: Gymnastics
Best Finish: Gold (2008 Beijing)

We're already well-versed on the rise and fall of Nastia Liukin, i.e. who was the individual all-around Champion in Beijing but failed to qualify for the 2012 team after announcing her comeback from retirement. Although she's not competing, Liukin still went to London as the athlete representative for Federation of International Gymnasts.