At ExCeL Exhibition Centre: Dallas welterweight Errol Spence Jr., who trains at Maple Avenue Gym, gets his first big test, facing No. 3 seed Vikas Krishan of India in a quarterfinal bout. U.S. medal favorite and three-time Olympian Rau'shee Warren is competing in the flyweight division against Nordine Oubaali of France in the round of 16.At the Aquatics Centre: Michael Phelps tries to pad his career medal haul when he goes for the final individual medal of his Olympic career in the 100-meter butterfly, where he's the defending Olympic champion. On Thursday, Phelps won a record 20th career Olympic medal (16 golds). Watch closely or you'll miss the men's 50-meter freestyle, nicknamed the "splash and dash." And teenager Missy Franklin, who already has two golds, is favored to add to her medal total in the women's 200-meter backstroke. At Olympic Stadium: The first day of track and field opens with medals in men's shot put -- and there are three strong U.S. contenders in Reese Hoffa, Christian Cantwell and Ryan Whiting. The women's heptathlon begins and prelims are scheduled in the women's 400 meters, featuring former Longhorn Sanya Richards-Ross. Medals will be awarded in the women's 10,000 meters. At City of Coventry Stadium: It's win or go home for the U.S. women's soccer team. The U.S., 3-0 in group play, faces New Zealand in the quarterfinals in the knockout stage of the tournament. Striker Abby Wambach scored a goal in each of the games. At the All England Club: The Olympic tournament reaches the semifinals in men's and women's singles. Wimbledon finalist and British hope Andy Murray faces Novak Djokovic of Serbia and Wimbledon champion Roger Federer of Switzerland plays Juan Martin del Potro of Argentina. Wimbledon champion Serena Williams plays Victoria Azarenka of Belarus. The other women's semifinal features two countrywomen, Maria Sharapova vs. Maria Kirilenko of Russia.