Tyson Gay will hope to challenge Usain Bolt at the World Championships
Tyson Gay swept to victory in the 100m at the Super Grand Prix in Stockholm in a time of 9.79 seconds.
The 26-year-old American's effort was a mere two-hundredths of a second slower than his world's best mark this season - set in Rome on 10 July.
He said: "This race proved that I am in form and was important in terms of the World Championships (15-23 August)."
In the 400m, America's Jeremy Wariner cruised to victory in 44.83 seconds ahead of Britain's Michael Bingham.
World champion Gay finished ahead of Darvis Patton (9.95), former world record holder Asafa Powell (9.98) and Churandy Martina (10.01).
Jamaican Usain Bolt holds the world record of 9.69, set at the 2008 Beijing Olympics, but Gay is still hopeful of upsetting the Olympic champion and world record holder in Berlin.
Meanwhile, America's Allyson Felix ran the fastest 200m of the season, winning in a time of 21.88 seconds ahead of the former season leader Debbie Ferguson.
"I was worried by the conditions," said Felix, referring to the cold, blustery night. "I wanted to work the bend and it went well."
Ferguson's time of 22.23 seconds was slightly faster than her previous best for 2009.
Despite two false starts, Cuban Olympic champion Dayron Robles won the 110m hurdles in 13.11 seconds.