Phelps, who has captured two medals in the 4x100 freestyle relay and 4x200 freestyle relay this summer, hasn't been as impressive in the 400-meter individual medley and the 200-meter butterfly.
After placing fourth in the 400-meter individual medley and seeing teammate Ryan Lochte capture the gold medal on Saturday, Phelps had the lead over South Africa's Chad Le Clos on Tuesday in the 200-meter butterfly before Le Clos overtook him in the final stretch.
Phelps ended up with the silver medal (1:53.01), flinging his cap to the side in the process, and everyone—including Le Clos—tried to grasp what had just happened.
This is not meant to bag Phelps, of course. He has the most medals in Olympic history with 19 (including 15 gold) and he's the greatest swimmer of all time.
On the other hand, you wonder what would have happened this summer if Phelps didn't have his teammates. He admitted losing focus after the 2008 Beijing Olympics and his times back that up.
For example, in the 200-meter butterfly four years ago, Phelps set the world record with a time of 1:52.03. Even in 2009, he broke his own record with a time of 1:51.51.
Then something happened.
Phelps recorded a 200-meter butterfly of 1:54.11 in the 2010 Pan Pacific Championships, as well as a time of 1:53.34 in the 2011 World Championships.
So while Phelps steadily improved after an uncharacteristic performance in the event in 2010, he obviously didn't recover enough when he lost the lead to Le Clos on Tuesday.
The reality is, this is the perfect Olympics for Phelps to retire because a slide would be expected if the 27-year-old continued to swim for much longer. His loss to Le Clos was evidence enough.
Will Phelps win an individual gold medal this summer? There's always a chance, given his supreme talent level.
But it's evident that he should retire while he's still on top after the 2012 Summer Games.
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