The Williams sisters' perfect run at the Olympics is over.
Venus and Serena Williams suffered their first-ever loss in doubles at the Olympics on Sunday, upset 6-3, 6-4 by the Czech duo of Lucie Safarova and Barbora Strycova in the first round in Rio.
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The American legends had won gold in 2000, 2008 and 2012; they did not participate in the 2004 Athens Olympics.
Though slowed a bit by age, they entered Rio as the top seed and were favored to play deep into the tournament.