Australia's Mollie O'Callaghan finished with a flourish to break the longest-standing world record in women's swimming, claiming the 200 meters freestyle title in a time of one minute, 52.85 seconds at the World Aquatics Championships on Wednesday. O'Callaghan, 19, broke the performance-enhancing bodysuit era mark of 1:52.98 set by Italian Federica Pellegrini at the 2009 worlds in Rome, and was 0.16 seconds ahead of silver medalist Ariarne Titmus of Australia in an extraordinary final.