Rising star Christian Coleman eased into the final of the 100m at the US World Championship trials as hurdler Keni Harrison laid down a marker to her rivals with the fastest time of the year.
Coleman, the fastest man in the world over 100m this season, clocked 10.04sec to comfortably win his semi-final at Sacramento's Hornet Stadium.
In the women's 100m semi-finals, 2016 Olympic silver medallist Tori Bowie cruised into her final in a time of 11.03sec.
Bowie was joined in the final by Allyson Felix, who is not expected to run the 100m at the World Championships in London. Felix edged into the final after finishing fifth fastest overall in a time of 11.22sec.
In the women's 100m hurdles, world record holder Keni Harrison impressed with 12.54sec, the fastest time in the world this season.
The 24-year-old is desperate to make up for the bitter disappointment of last year when she missed out on the Olympics after finishing sixth at the trials in Oregon.
Friday was Harrison's first race since breaking her hand at a meeting in Doha in June.
"I wanted to come out here and put a good number down," said Harrison, who ran with a metal pin in her left hand.
A few weeks after missing out on a place to Rio in 2016, Harrison smashed Yordanka Donkova's 28-year-old world record, clocking 12.20sec at a meeting in London.
American women have achieved remarkable dominance in the 100m hurdles in recent years and in 2016 completed a clean sweep of medals in Rio.
Brianna Rollins, the gold medallist in Rio, is not competing in Sacramento following a one-year ban for missing three drug tests.