Friday went about as well for the United States in swimming as any day could for a single nation in a single sport. Of the four finals contested on Friday, U.S. swimmers won three of them.
In the process, the U.S. Olympic swimming torch was passed from one generation to the next.
For one of the winners, the legendary Michael Phelps, his gold in the 100-meter butterfly was the perfect ending to his final individual swim as an Olympian. For the other two U.S. winners, Missy Franklin and Katie Ledecky, earning gold medals in London marks only the beginning of what could be two legendary careers.
Phelps, competing in his fourth and final Olympics as a 27-year-old, extended his records as the most decorated Olympian to 17 gold medals and 21 overall medals with his win Friday. After a slow start with a fourth-place finish in Saturday’s 400-meter individual medley, Phelps made London another Olympics to remember for him by winning three golds in three consecutive events.
Phelps has a chance for a picture-perfect ending and fourth consecutive gold Saturday, when he will swim the butterfly leg of the 4x100-meter medley relay final.
Phelps reiterated on Thursday that his career is about to come to an end, saying that he will "definitely retire from swimming competitions after London Olympics," according to Xinhua.
With his retirement from swimming, the time is right for new, young stars to emerge in the sport.
Franklin and Ledecky, who are both still in high school, could be the next superstars of U.S. swimming.
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Franklin, 17 years old, has had a remarkable beginning to her Olympic career. Franklin’s best moment yet came on Friday, when she set a world record of 2 minutes, 4.06 seconds in the 200-meter backstroke to earn her third gold and fourth overall medal in London.
Phelps knows exactly what it is like to be in their shoes; at only 15 years old, Phelps competed at the 2000 Olympic Games in Sydney.
Phelps, however, did not win a medal in his first Games.
In that capacity, Franklin and Ledecky are already ahead of him as teenagers in their first Olympic competition, and they should have many more Games and Olympic medals in their future.
Of course, Phelps followed up his first Olympics with a remarkable showing at the 2004 Games in Athens, where he won six golds and eight medals overall.
It is time, however, for a changing of the guard in U.S. swimming.
On the men’s side, Ryan Lochte is in line to become the sport’s biggest star, after winning two golds and five medals overall in London. Lochte is actually older than Phelps, at 28 years old, but unlike Phelps, Lochte plans to compete at the 2016 Games in Rio de Janeiro, according to the New York Times.
Other young stars on the women’s side include 22-year-old Allison Schmitt, who is tied with Franklin thus far for the most women’s swimming medals in London with four, and 19-year-old Elizabeth Beisel, who earned two medals in her second Games.
Yes, the changing of the guard from Phelps’ era of dominance started to take place in London, but not before Phelps had one more run as the superstar of the U.S. Olympic team.
Dan Hope is a Bleacher Report Featured Columnist covering the 2012 Olympic Games. Follow him on Twitter @Dan_Hope.