The American Michael Phelps and the Australian Jessicah Schipper broke the world records in the men's and women's 200 metres butterfly at the Pan Pacific championships in Victoria, Canada, on Thursday night.
Phelps, 21, broke his own 200m butterfly mark clocking 1min 53.80sec to shave off 0.13sec from his previous best which he set in Barcelona in 2003. Phelps, who won six gold medals at the Athens Olympics in 2004, was pushed by Japan's Ryuichi Shibata until the final 50 metres before the American surged clear. Shibata finished in second place in 1:55.82.
"It's a good start to the meet," Phelps said afterwards. "I've wanted to do a best time in that event for a while now. I saw the other guys do well this morning, so I knew it would be close at the 150.
"But [my coach] Bob [Bowman] and I were talking about having a strong kick off the last wall. I did that and was able to build some good momentum. When the crowd is cheering like that you always know something good is happening."
Schipper, the 100m butterfly world champion, clocked world-record splits throughout the race before winning in 2min 5.40sec. Her time was 0.21sec quicker than the previous record set at last year's world championship final in Montreal by Poland's Otylia Jedrzejczak.
Schipper finished second in that race behind the Pole, who controversially kept the title and record despite television footage showing that she touched the wall with just one hand.
"I heard the crowd, and it really helped me. It's just amazing to break the world record, I can't believe it," Schipper said.
Schipper finished well clear of the field in her race, with the Japanese swimmer Yuko Nakanishi claiming second place in 2:06.52 and her team-mate Yurie Yano coming home in third.