Team GB's Anyika Onuora has missed out on automatic qualification after finishing in fifth place of the second heat in the women's 100m sprint.
Onuora ran a time of 11.41s, six hundredths of a second behind the third qualifying spot.
Meanwhile, Team USA's Carmela Jeter cruised away from the field to take the second heat in 10.83s.
Olga Bludova and Sheniqua Ferguson filled the final automatic qualifying spots, cementing their place in the 100m semi-final.