The first night of world championship swimming competitions saw six world record tumble at the Foro Italico on Sunday. Italy's Federica Pellegrini made home fans proud by beating her own world mark to win the women's 400m freestyle, and German Paul Biedermann also brought down a world record as he won the men's 400m freestyle final.
The Dutch women's 4x100m freestyle team, the Olympic champions in 2008, shattered their world record to win the title, despite a brilliant swim by German Britta Steffen who set an individual 100m freestyle mark in the lead-off leg at the same race.
Sweden's Sarah Sjostrom set a new world standard in the women's 100m butterfly while American Ariana Kukors bettered the women's 200m individual medley world mark.
Led by Michael Phelps, the United States beat Russia for the men's 4x100m freestyle relay gold, with France finishing third.