American Tyson Gay recovered from a poor start to beat rival Asafa Powell over 100m in 9.93 seconds at the British Grand Prix in Gateshead.
Jamaican Powell started well but Gay fought back despite a slight headwind to win the Diamond League event.
It was Olympic and world silver medallist Gay's seasonal debut over 100m following a hamstring problem.
Phillips Idowu and Lisa Dobriskey won their events while Jessica Ennis had a mixed day on her return after illness.
Powell, returning to the track where he equalled his former world-record time of 9.77 seconds in 2006, had promised a fast time but failed to deliver in the final.
Gay had won the opening heat in an impressive 9.96 seconds and managed to go even faster to seal his victory.
"I feel good. He's one of my favourite competitors and I managed to get him today," said Gay.
"I really had to stretch to the finish line and he didn't see me coming so I got the victory.
"The hamstring is still tight and that is something I am going to have to work on."