In many cases the United States Olympic swimming trials are a tougher meet than the Olympics competition, with some of the world's best swimmers forced to compete for the top two spots in most events in order to make the 26-athlete roster.
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While the rest of the world's teams have their rosters set for Rio, the U.S. has eight days of preliminary, semifinal and final heats to determine its squad in front of a sold-out crowd of more than 10,000 people each night.