The winningest Olympian ever is still looking for his first gold of the London Games, getting out-touched at the wall by South Africa's Chad le Clos. Phelps flipped away his cap in disgust when he saw a "2'' beside his name, knowing he had blown it at the end by trying to glide to the wall instead of taking one more stroke.
Le Clos won in a time of 1 minute, 52.96 seconds. Phelps finished in 1:53.01, while Japan's Takeshi Matsuda took the bronze in 1:53.21.
Despite the disappointment, Phelps tied Soviet gymnast Larisa Latynina as the career leader with 18 medals.