The expected Great CityGames duel between Aries Merritt and Andrew Pozzi over 110m hurdles produced an unexpected winner with Poland's Damian Czykier taking an error-strewn race.
American world record-holder Merrit and Britain's world indoor champion Pozzi both clattered hurdles, finishing well off the winner's 13.67 seconds.
Six-time Olympic champion Allyson Felix was beaten by in-form Marie-Josee Ta Lou in the 150m in Manchester.
Ivorian Ta Lou won in 16.60 seconds.
The world silver medallist at both 100m and 200m, Ta Lou's explosive start gave American Felix too much to make up.
Britain's Harry Aikines-Aryeetey edged a tight 100m on the pop-up track along Deansgate, dipping two-hundredths of a second ahead of compatriot Richard Kilty to win in 10.35 seconds.
Sophie Hahn - the Olympic, world and European T38 champion - beat Georgie Hermitage, who runs in the T37 category, in a women's race involving athletes from both classifications.
Leon Reid, who took Commonwealth Games 200m bronze for Northern Ireland last month, secured a hard-won victory in the 150m, holding off the Netherlands' Solomon Bockaire.
American Bershawn Jackson won the 200m hurdles in 22.59 seconds before explaining that the loss of his 53-year-old father from a heart attack in October 2016 is behind his decision to leave the sport at the end of the season.
"Mentally I am not there any more, it is time for a new chapter," the 35-year-old former 400m hurdles world champion told BBC Two.
British athletes were beaten to victory in the two field events held in nearby Albert's Square.
Commonwealth Games bronze medallist Luke Cutts was second to France's Stanley Joseph in the pole vault, while Eloyse Lesueur of France took the long jump ahead of Rio 2016 finalist Jazmin Sawyers.