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US swimmer Michael Phelps speaks at a press conference.

Lots of action coming up in the Olympics today. The U.S. men's basketball team goes up against Nigeria. So far, the U.S. team has been blowing out the competition. And in tennis, players move into the quarterfinal round of the singles competition.

Plus boxing, rowing, cycling, and yes, dressage. Rafalca, the horse part-owned by Ann Romney is featured in the equestrian event today.

And then there's Michael Phelps. Having already broken a record after winning his 19th Olympic medal — fifteen of them gold — he's set to race in 200 meter individual medley later today. A Martinez caught up with one of Michael Phelps' teammates, Jason Lezak, to talk about swimming and Phelps' role on the team.

Guest:

A Martinez, KPCC reporter