Christian Coleman equalled the fastest 100m time in the world this year to win in Xiamen.
The American matched the 9.83 seconds ran by compatriot Noah Lyles at the World Championships and Zharnel Hughes' British record set in June.
Coleman finished fifth in the world final but held on this time in China to hold off Jamaica's Kishane Thompson.
Melissa Courtney-Bryant was fourth in the women's 1500m - the best British result at the Diamond League meeting.
Ethiopia's Lemlem Hailu sprinted away from Kenya's Nelly Chepchirchir in the closing straight to win a high-quality race that saw four women run under four minutes.
Linden Hall, of Australia, pipped Courtney-Bryant to third place as the 30-year-old Briton finished in 3mins 58.22secs.
But it was the men's 100m that really lit up the meeting.
Coleman powered to the front early in the race and maintained his form to hold off a charging Thompson by just two hundredths of a second, as USA's 2022 world champion Fred Kerley finished third.
"It hurt a little bit but I knew what I was capable of doing and I knew what I was ready to do," said 2019 world 100m champion Coleman, as he reflected on his performance at last month's World Championships.
"Then my mind transitioned into the next opportunity for success. I knew coming here it would be a world-class field and an opportunity for me to bounce back."
Kenya's Emmanuel Wanyonyi was another standout performer in the men's 800m, beating Canada's reigning world champion Marco Arop by four hundredths of a second to win in a world-leading time of 1:43.20. Britain's Daniel Rowdon and Ben Pattison finished fifth and ninth, respectively.
Jamaican Olympic champion Hansle Parchment won the men's 110m hurdles in 12.96 secs, with American Daniel Roberts finishing strongly to claim second ahead of world champion Grant Holloway, who fell to only his second defeat of 2023.
Elsewhere, Kenya's Beatrice Chebet won the women's 3,000m in 8:24.05, the world's best time this year, while Britain's Victoria Ohuruogu was fifth in the women's 400m, which was won by the Dominican Republic's Marileidy Paulino.
The Diamond League series moves on to Brussels on 8 September and concludes in the United States with the finals in Eugene, Oregon, on 16-17 September.