Russian Denis Pankratov eclipsed his own world record in the 100-meter butterfly final Wednesday to complete a golden double.
And Hungarians finished 1-2 in the 200-meter breaststroke with world champion Norbert Rozsa winning the gold.
Pankratov swam more than half the first length of the 50-meter Georgia Tech pool below the surface and hit the turn in 24.19 seconds, well inside world-record pace.
Australia's Scott Miller, the fastest qualifier, staged a magnificent challenge on the return length but could not catch Pankratov.
Pankratov won in 52.27 seconds, 0.05 of a second inside the world mark he set at the European championships in Vienna last August. He won the 200 butterfly Monday.
Miller claimed the silver in 52.53 and Vladislav Kulikov took the bronze in 53.13.
"He was just too good," Miller said. "Twenty meters out he seemed to find something that I didn't think he had."
Rozsa, who failed to make the final of Saturday's 100 breaststroke, made dramatic amends when he and fellow Hungarian Karoly Guttler overtook Russian pace-setter Andrei Korneyev on the final length in the 200 breaststroke.
Korneyev took the race out fast and for the first 100 meters was inside the world-record pace American Mike Barrowman set at the 1992 Olympics. But he could not keep the Hungarians at bay and Rozsa, double silver medalist in Barcelona in 1992, finished in 2:12.57.
Largo's Tucker gets medal
Largo's Scott Tucker, a Seminole High graduate and a swimmer for Auburn, will receive a gold medal for the 400-meter freestyle relay won by Americans on Tuesday.
Tucker did not swim in the final of the 400 freestyle relay but swam the second leg of the preliminary heat to earn the medal.