Michael Phelps wins men 's 100m butterfly for 17th Olympic gold medal . Missy Franklin breaks world record to win women 's 200m backstroke . Frenchman Florent Manaudou prevented a U.S. clean sweep of gold with a shock win in the men 's 50m freestyle . Katie Ledecky shocks home favorite Rebecca Adlington in women 's 800m . Comment:
Michael Phelps wins men 's 100m butterfly for 17th Olympic gold medal . Missy Franklin breaks world record to win women 's 200m backstroke . Katie Ledecky shocks home favorite Rebecca Adlington in women 's 800m . Comment: