Great Britain's Eilidh Child exited the women's 400m hurdles at the semi-final stage this evening.
Running from lane nine, Child had to go out hard to stand any chance of qualifying for Wednesday's final.
She did just that, but appeared to tire with 150m remaining and ended up in seventh place.
Muizat Ajoke Odumosu won the race in 54.40s, which is a Nigerian record. Georganne Moline took the second automatic qualifying spot.