Justin Gatlin continued his preparations for next month's World Championships by winning the 100m at the Diamond League Meeting in Lausanne on Thursday.
The American won with a time of 9.75s to beat rivals Asafa Powell and Tyson Gay, who both clocked 9.92s.
Gatlin's time was 0.01s behind his personal best, which he set in May during a Diamond League meeting in Doha.
"It's not a message to anybody," Gatlin told reporters. "Usain [Bolt] is a great opponent, so it's on me to go out and give him the best challenge I can. Hopefully he will be healthy and ready to go for the world championships."
Gatlin, Powell and Gay have all previously served bans for doping.