Three-time gold medalists Serena and Venus Williams had their hopes for winning a fourth consecutive Olympic title dashed as the doubles duo lost for the first time Sunday at the Rio Games. In a huge upset, the sisters lost in the first round to the Czech Republic’s Lucie Safarova and Barbora Strycova. Out of 16 Olympic matches played together, this was the first time the tennis stars lost, with a score of 6-3 6-4. “We played terrible and it showed in the results,” Serena said after the match. U.S. Women’s Tennis Coach Mary Joe Fernández said a day earlier that Venus’s performance might suffer because she “had been ill for a few days with a bad virus” prior to the Games. The news came amid a string of upsets: Men’s world No. 1 player Novak Djokovic lost in straight sets in his opening-round match, leaving center court in tears; and Wimbledon champion Andy Murray and and his brother Jamie fell in men’s doubles to a Brazilian duo.