The eight qualifiers for the women's 100 metre final were separated by just eight hundredths of a second, two Jamaicans leading the way.
Murielle Ahoure failed to reach the final of the women's 100 metres at Rio 2016, as Elaine Thompson and reigning champion Shelly-Ann Fraser-Pryce topped a tightly bunched list of qualifiers.
Ahoure, Ivory Coast's flag bearer, came into the Games having posted the equal-third-best time in the world this year, 10.78 seconds.
However, the 28-year-old could only clock 11.01secs in the first semi-final, enough for fourth place, and therefore missed out on the final, scheduled for 22:37 local time (01:37 GMT).
Michelle-Lee Ahye and Tori Bowie each clocked 10.90secs in Ahoure's race, while Jamaica's Fraser-Pryce looked in fine form as she won semi-final two with a season's best time of 10.88secs, despite easing up in the closing stage. Dafne Schippers was close behind in 10.90.
Yet Thompson - the fastest woman in the world in 2016 - was arguably the most impressive qualifier, as she matched Fraser-Pryce's time with ease, the United States' English Gardner (10.90) also progressing comfortably.
The two fastest losers, also through to the final, were Marie-Josee Ta Lou (10.94) and a third Jamaican, Christania Williams (10.96).