Phelps wins twice at U.S. championships

INDIANAPOLIS, July 9 (UPI) -- Olympic superstar Michael Phelps won two races and Aaron Peirsol reclaimed his 100-meter backstroke world record Wednesday at the U.S. Swimming Championships.

Phelps, winner of 14 Olympic gold medals, captured both the 200-meter freestyle and the 200-meter butterfly. He was timed in 1:44.23 in the freestyle, 0.72 of a second ahead of David Walters.

In the butterfly, Phelps posted a time of 1:52.76 to easily defeat Tyler Clary.

Peirsol turned in a 51.94 in the 100-meter backstroke, lowering the world mark set this month by Aschwin Wildeboer Faber of Spain. Peirsol won the event at each of the last two Olympics.

In the other finals, Hayley McGregory captured the women's 100-meter backstroke in 1:00.07 and Dana Vollmer, an Olympic gold medalist in Athens, won the women's 200-meter freestyle in 1:56.20.

This year's national championships are being used as the qualifying meet for the world championships in Rome this month.