Swimming
The marquee sport of the first week comes to a close as does, probably, the career of Michael Phelps, perhaps the greatest Olympic athlete of all time. You can expect to see him in the 4X100 medley relay, a race that should close the book on an Olympic career that started 16 years ago in Sydney. Also back will be Simone Manuel, the first black woman swimmer from the U.S. to win a gold medal. She'll also be in the 4X100 medley relay and the women's 50 freestyle.
Track and Field
It'll be over in a flash but the world's fastest woman will be decided on the second day of track and field competition. The women's 100 will feature Americans English Gardner, Tianna Bartoletta and Tori Bowe to go along with Elaine Thompson of Jamaica and Murielle Ahoure of the Ivory Coast. You'll also get your first look at Usain Bolt, who will be running in qualifying for the men's 100 meters, which will be contested on Sunday night.
Tennis
Everyone wanted to see Serena Williams in this position but instead will have to settle to see if Monica Puig can win Puerto Rico's first ever gold medal.Sshe'll be going up against Angelique Kerber of Germany. The men's side of the draw still has some star power left with Andy Murray of Britain playing Kei Nishikori. The winner will play either Rafael Nadal of Spain or Juan Martin del Potro of Argentina.
