Olympic champion Sydney McLaughlin breaks her own world record in 400m hurdles - ESPN

-- Olympic champion Sydney McLaughlin bested her own world record in the 400-meter hurdles at the U.S.

outdoor track and field championships Saturday.

The top three finishers in each event at the national championships will represent the United States in the world outdoor championships, also at Eugene's Hayward Field, next month.

It is the first time that track and field's biggest event outside of the Olympics will be held on American soil.

Allyson Felix, the most decorated woman in track history, finished sixth in the 400 meters, in what was her final national championship race.

Dalilah Muhammad sat out of the race because of a slight injury, but she has already qualified for the world championships as the defending champion in the event.

Richardson, known for her ever-changing hair color and long nails, did not qualify for the 100 final, even though she was among the favorites after winning the event at the Olympic trials last year.

Kentucky's Abby Steiner, who set a collegiate record in the 200 meters at the NCAA track and field championships, had the best time in the heats at 22.14.