Among the six finals of the eighth day, the men's high jump final helped fill out the stadium for the first time as Qatari Mutaz Essa Barshim won a high quality contest for the host nation. Barshim, Mikhail Akimenko and Ilya Ivanyuk all cleared before the home athlete topped to win his country's first gold of the event. In the women's 400 metres hurdles final, Americans Dalilah Muhammad and Sydney McLaughlin turned the race into a duel which resulted in Olympic champion Muhammad setting a world record of 52.16 seconds to hold off 20-year-old McLaughlin, who ran the third fastest time ever. Ethiopian Lamecha Girma attempted to break Kenya's winning streak in the men's steeplechase final but was edged out on the line by Kenya's defending champion Conseslus Kipruto, with one hundredth of a second separating the two. Steven Gardiner of the Bahamas had a dominant run to win the men's 400 metres final, finishing over half a second ahead of the field and setting a Bahamian record of 43.48 seconds. Gardiner's presence was only possible due to a public fund-raising campaign for his national team, as Hurricane Dorian had devastated the Caribbean nation just one month earlier. The women's discus final was a Cuban affair between Yaime Pérez and Denia Caballero, with Pérez ultimately winning the gold with a fifth round effort of . The first round of the men's and women's 4 × 100 metres relay saw athletes run an African record, a South American record and three national records. Toshikazu Yamanishi took the gold medal in the men's 20 km walk in the overnight session.