Jamaican Yohan Blake, the 2012 Olympic 100 and 200 metres silver medallist, is down playing the seriousness of a groin problem which ruled him out of Sunday's 100m at the Diamond League meeting in Rabat, Morocco.
Olympic champions Shaunae Miller-Uibo and Elaine Thompson boosted their hopes of global titles next month with super-swift sprints at the tenth International Association of Athletics Federations Diamond League meeting of the season in Rabat, but for Rio 2016 winners Conseslus Kipruto and Thiago Braz the evening was anything but uplifting.
Soufiane El Bakkali of Morocco wins in the Men's 3000m Steeplechase in the time of 8.05.12.
Ujah, 23, achieved a season's best of 9.98 seconds and beat the record of 10.12 held by American Justin Gatlin. The next Diamond League meeting is in Monaco on July 21.
Miller-Uibo eased to a second victory of the season and set another meeting record with a circuit of 49.80, finishing nearly a second before runner-up Natasha Hastings.
Germany's Raphael Holzdeppe, an equally undefeated world champion in 2013, was second ahead of another Pole, Piotr Lisek, with both men clearing 5.70 - 10 centimetres more than the current world champion Shawn Barber of Canada.
Botswana's Nijel Amos was rewarded for a bold run in the 800m and will head for the second final meeting in Brussels on September after winning in 1:43.91.
American Ryan Crouser won with a throw of 22.47 metres. Barbora Spotakova of the Czech Republic won the event with a distance of 63.73, Slovenia's Martina Ratej was second at 62.46, followed by Tatsiana Khaladovich of Belarus at 62.38.
In the men's high jump, Ukrainian Andriy Protsenko won with a leap of 2.27 metres.
Jamaica's Kimberley Williams and Tajay Gayle will be participating in the women's triple jump and men's long, respectively.
Ivory Coast's Ben Youssef Meite was second (10:01) with fellow Brit Nethaneel Mitchell Blake (10:18) in third place.
Jackson will have her hands full against Miller-Uibo, who has two sub-50 clockings this season of 49.77 and 49.86, and American Hayes whose 49.72 makes her the fastest in the field and second quickest in the world behind Allyson Felix's 49.65.