American Kim Conley runs a 5-second personal best but fails to qualify for Friday's final.
She's been dominating the indoor 300m since 2004.
She says she's fit and confident.
Many world-leading performances posted Saturday night in Boston.
Kenyan women go 1-2 in the 5,000-meter final.
American-record holder Molly Huddle fails to advance.
The world championships are her "big goal" for the season.
The American 10,000m record holder is confident of her chances.
On July 17, she will try to qualify for the 10,000m.
Meseret Defar is going after her own mark.