The 30-year-old from Boulder, Colorado, the bronze medallist at the Rio 2016 Olympics and the owner of world gold and silver medals from 2017 and 2019 respectively, finished in 9min 09.41 at the newly re-built Hayward Field as the trials resumed after two rest days.

Courtney Frerichs, who took silver behind Coburn at the 2017 World Championships, was second in 9:11.79 and the third automatic qualifying place for Tokyo 2020 went to Val Constien, who clocked 9:18.34.

Constien took 7.19sec off her personal best after Leah Falland had tripped and fallen after clearing a barrier with just under two laps left.

In today's other final, the women's shot put, Jessica Ramsey won with 20.12 metres, improving on her personal best by almost a metre, to go second in this year's world list behind double world champion Gong Lijao of China.

Ramsey will be joined in Tokyo by 2016 Olympian Raven Saunders, who threw 19.96m, and Adelaide Aquilla, who reached 18.95m.

Rio 2016 gold medallist Michelle Carter watched the competition from the stands after undergoing surgery on June 3 to remove what turned out to be a benign tumour from her right ankle.

In qualifying action, Sean Burrell, who broke the 37-year-old world under-20 record in the 400m hurdles as he clocked 47.85sec in winning the National Collegiate Athletic Association title on this track on June 11, came to grief with a fall over the eighth hurdle in his heat.

Rai Benjamin, who heads this year's world lists with 47.13, reached the semi-finals without a problem.

Rio 2016 gold medallist Kerron Clement, 35, who has raced very little in the last two years, failed to earn the qualifying time required to take part in the trials. 

Another 35-year-old US Olympic champion, Allyson Felix, who has already made the team in the 400m, qualified tenth fastest for the 200m semi-finals, despite commenting that her legs were "a little rusty".

Gabby Thomas, who has already earned a place in the 4x100m relay pool, produced the fastest time of the year so far in clocking a personal best of 21.98.

Brittney Reese and Tianna Bartoletta, the Olympic long jump champions in 2012 and 2016 respectively, both reached Saturday's (June 26) final.

Another London 2012 champion, pole vaulter Jenn Suhr, reached the 12-strong final on Saturday along with Rio 2016 silver medallist and world indoor champion Sandi Morris.

The world's top three women's hammer throwers - DeAnna Price, Brooke Andersen and Gwen Berry - were among 12 qualifiers into Saturday's final.

The Olympic Trials continue tomorrow with men's finals in the 3,000m steeplechase and discus, as well as the semi-finals of the women's 200m and 800m and men's 400m hurdles and 1500m.