Olympic and world champion Cesar Cielo of Brazil set a world record of 20.91 seconds in the men's 50 meters freestyle in Sao Paulo on Friday. The old mark was 20.94 by Frederick Bousquet of France set on April 26 in Montpellier, France.
Cielo also holds the world record for 100 meters of 46.91 seconds, which he set on July 30 in Rome.
The 22-year-old Brazilian won the gold medal in the 50 freestyle in last year's Beijing Olympics.
Cielo's coach had suggested him wearing a Speedo swimsuit instead of his Unitard Saturday in the last day of meet as the Unitard will be prohibited in 2010.
But Cielo insisted on using the Unitard suit.
"I have all of next year to get used to Speedo. Today was not the day to return to the Speedo ... I will be ready for next year's changes," he said.