What to watch: Day 12 at the Olympics

Here's your guide to the top events taking place in London on Wednesday, Aug. 8. Check out the schedule here.

The next gold medalists in women's beach volleyball will be American — but which Americans? Will it be two-time defending Olympic champions Misty May-Treanor and Kerri Walsh Jennings, who beat the No. 2 Chinese team in the semifinals, or will it be the "other" Americans, April Ross and Jennifer Kessy, who upset the top-seeded Brazilians and are looking to end May-Treanor and Walsh Jennings' reign? That will be determined at the 4 p.m. ET match, which you can follow live with Yahoo! Sports.

The marquee track event will be the women's 200-meter race at 4 p.m. ET. The event features one of the fastest fields in Olympic history and continues the sprint rivalry between the U.S. and Jamaica, which together boast five runners in the eight-woman field.

[ Video: Huge showdown looms in women's 200 meters ]

The race will include the top-three finishers of the 100m race -- Jamaica's Shelly-Ann Fraser-Pryce, USA's Carmelita Jeter and Jamaica's Veronica Campbell-Brown -- and the U.S. winner of the 400 meters, Sanya Richards-Ross. The favorite, however, is American Allyson Felix, who finished fifth in the 100 meters and is seeking her first medal at these Games.

In men's basketball, Team USA takes on Australia at 5:15 p.m ET in the quarterfinals. The other games are Lithuania vs. Russia (9 a.m. ET), Spain vs. France (11:15 a.m. ET), and Argentina vs. Brazil (3 p.m. ET).

In other quarterfinal action, the U.S. men's volleyball squad plays Italy at 11 a.m. ET, and the U.S. men's water polo team faces off against Croatia at 3 p.m. ET.

Boxing will see its first medal matches. Marlen Esparza of the U.S. will battle China's Cancan Ren in an 8:30 a.m. ET semifinal in the flyweight (under 51 kilograms) division, while 17-year-old American Claressa Shields takes on Marina Volnova of Kazakhstan in the semifinals of the middleweight (60-75 kg) division at 9:30 a.m. ET.

[ Video: Why can't women break world records in track? ]

In other track news, men's decathlon gets its start with the 100 meters at 5:10 a.m. ET, the long jump at 6:10 a.m. ET, the shot put at 8:10 a.m. ET, the high jump at 1 p.m. ET, and finishes with the 400 meters at 4:30 p.m. ET. American Ashton Eaton will try to replicate his world-record-setting performance at U.S. track trials, while countryman Trey Hardee will also make his run for the podium.

As for medal events, the U.S. has three women in the eight-woman 400m hurdles at 3:45 p.m. ET and two women in the 12-person long jump finals at 3:05 p.m. ET, while the men's 100m hurdles will hold semifinals at 2:15 p.m. ET, culminating in the finals at 4:15 p.m. ET. Aries Merritt is the U.S.'s best hope for a medal in that race.

There will also be medal events in canoe and kayaking, equestrian, sailing, table tennis, taekwondo, and wrestling. Check out their schedules here.

More Olympics coverage on Yahoo! Sports:

Related Olympics coverage on Yahoo! Sports:
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• Elite Athlete Workouts: U.S. volleyball star Kerri Walsh goes high-tech to gain the edge