American Justin Gatlin claimed an impressive win in the Diamond League 100m in Shanghai in 9.94 seconds.
Qatar's Femi Ogunode, the quickest man this year after running 9.91 in Florida in April, was second in 10.07.
Gatlin, 34, ran the five fastest times in 2015 but lost to Usain Bolt in the World Championship final.
In the 800m, Olympic champion and world record holder David Rudisha was fifth in one minute 46.24 seconds as fellow Kenyan Ferguson Rotich won in 1:45.68.
Rudisha led at the 600m stage but was beaten to the line by three compatriots, plus fourth-placed Thijmen Kupers of the Netherlands, with Britain's Michael Rimmer ninth in 1:47.44.
It was Gatlin's first sub-10 second run of the year, having run 10.02 in Japan last weekend.
Omar McLeod ran a world leading 12.98, one hundredth of a second outside his personal best, to win the 110m hurdles from fellow Jamaican Hansle Parchment.
Britain's Lorraine Ugen collected two points in the Diamond Race by finishing fifth in the women's long jump with 6.55m. Serb Ivana Spanovic jumped 6.95m to win.
The men's long jump was won by China's Gao Xinglong with 8.14m, while Britain's Dan Bramble was eighth with 7.75m.
Jade Lally was eighth in the women's discuss after a throw of 58.51m as Croatia's Sandra Perkovic won with 70.88m, the best in the world this year.