The US team suffered a double blow on the opening day of the IAAF World Championships on Friday when pole vaulter Jennifer Suhr and long jumper Jeff Henderson, both Olympic champions and among the favourites in London, failed to qualify for their respective finals.
Suhr, who won gold in London in 2012 and silver at the Moscow worlds a year later and is the reigning world indoor champion, failed to clear a height as just one vaulter, Ekaterina Stefanidi of Greece, went over the official qualification mark of 4.60m.
"It's three no jumps," said the 35-year-old Suhr, who has a personal best of 4.91m.
"I thought I made the first one but it just nicked off, so that was disappointing.
"Right now, I don't want to think about this too much as a bad experience because 2012 was such a good one for me.
"Maybe I'll have some time off because it has been a long 12 months. I just need a little bit of time to relax and come back stronger."
Henderson, who won gold at last summer's Rio Olympics, managed a best of only 7.84m, far off his personal best of 8.58 set in 2015 and season's best of 8.28.
"It's not what I wanted at all, I wanted to do better but I guess it's harder to come back after (winning Olympic gold) last year," said the 28-year-old, who no marked in his second qualifying jump after landing 7.74m in his first.
"I'm kind of sad I didn't get to go out there and get what I wanted to, but I guess I'll take something from it for next time.
"It's been a long year. I didn't really get much training compared to last year, but I'll be back hungry and stronger next year: you'll see the Jeff Henderson you saw previously."
© 2017 AFP