Britain’s Zharnel Hughes beat 2011 world champion Yohan Blake and American Tyson Gay to win the Boston Games 100m.
Hughes, 22, won in 9.99 seconds with South African Akani Simbine second, Blake third and Gay fourth.
It is the first time he has run sub-10 seconds but the time will not count as he was aided by a 2.4m/sec tailwind.
Last month, Hughes finished first in the Commonwealth Games 200m but was disqualified for impeding gold medallist Jereem Richards.
The sprint races in Boston were taking place on a special 200m straight track.
Britain’s Nethaneel Mitchell-Blake finished second in the 150m behind 20-year-old American Noah Lyles.