LONDON -- Americans men and women snatched three more gold medals in the pool today at the London Olympic games.
Michael Phelps won the 100-meter butterfly for the record 17th gold and 21st medal overall in his Olympic career.
In the final individual race of his career, Phelps was next to last at the turn but then produced his usual furious finish to clock 51.21 seconds.
Chad le Clos of South Africa and Evgeny Korotyshkin of Russia touched in 51.44 to share the silver medal.
Phelps will end his career with the 4x100 medley relay Saturday.
American teenager Missy Franklin set a world record in the 200-meter backstroke for her third gold and fourth medal overall at the London games.
Franklin clocked 2 minutes, 4.06 seconds, 0.75 quicker than the mark set by Kirsty Coventry of Zimbabwe at the 2009 world championships in Rome in a now-banned bodysuit.
It was the seventh world record of the games.
Anastasia Zueva of Russia touched in 2:05.92 to take the silver medal and Elizabeth Beisel of the United States finished in 2:06.55 to take bronze.
And 15-year-old Katie Ledecky won the 800-meter freestyle for the United States.
The youngest member of the U.S. swim team narrowly missed a world record in the grueling race, falling off pace on the last lap and finishing in 8 minutes, 14.63 seconds.
Mireia Belmonte Garcia of Spain touched in 8:18.76 to take the silver medal and defending champion Rebecca Adlington of host Britain finished in 8:20.32 for bronze.
Adlington set the world record of 8:14.10 at the 2008 Beijing Games.