Tyson Gay ran the second fastest 100-metre time this year on Thursday, clocking 9.79 seconds to win at the Athletissima Diamond League meet in Lausanne, Switzerland.
Only Gay's world-leading 9.75 to take the U.S. Nationals title has been faster in this world championships season, just five weeks before the main event in Moscow.
Usain Bolt, the Olympic champion and world record holder, has a season's best so far of 9.94 set at the Jamaican nationals last month.
Dylan Armstrong of Kamloops, B.C., threw a season best 20.75 metres in the shot put to finish third in the event. Americans Ryan Whiting and Reese Hoffa were 1-2.
Sheila Reid of Newmarket, Ont., was seventh in the women's 1,500 metres.
The 30-year-old Gay reacted fast to the starting gun yet only pulled away from former world record holder Asafa Powell of Jamaica in the final 40 metres.
Powell clocked his season's best time of 9.88 — bettered only by Gay in 2013 — to finish second, while American Michael Rodgers was third in 9.96.
Veteran Kim Collins, the 2003 world champion from St. Kitts and Nevis, set a personal best aged 37 of 9.97 to place fourth.
The standout performance was produced by high jumper Bohdan Bondarenko who threatened the 20-year-old world record set by Javier Sotomayor of Cuba.
Bondarenko cleared a world season-leading height of 2.41 metres — five centimetres better than his previous best set last Sunday at Birmingham, England — before taking aim at Sotomayor's hallowed 2.45 mark.
"I can't explain that progression. It's simply fantastic for me," the 23-year-old Ukrainian said.
With the bar set at 2.46, Bondarenko only just failed at his first of three unsuccessful attempts.
American Erik Kynard, the Olympic silver medallist, also cleared a personal best, at 2.37, to place second.
Two more athletes set world-leading marks on a cool and breezy evening.
David Oliver timed 13.03 in the 110 hurdles, leading an American sweep of the first four places. World champion Jason Richardson ran his season-best of 13.20 to place second.
Olympic discus champion Sandra Perkovic extended her own 2013 mark with a throw of 68.96 metres, 48 centimetres beyond her best at the New York Diamond League meet in May.
A surprise winner in the women's 200 was Mariya Ryemyen of Ukraine, surging late past a strong American entry in a time of 22.61 seconds.
New U.S. champion Kimberlyn Duncan was third, timing 22.73 on her debut run in an individual race in Europe.