Irvine: Katie Ledecky swam a "pretty close to perfect" race on Saturday to seize the 400m freestyle world record at the US Championships.


Katie Ledecky 

The 17-year-old schoolgirl powered to victory in a dazzling 3min 58.86sec, eclipsing the prior world mark of 3:59.15 set by Italy's Federica Pellegrini in 2009 in the era of now-banned high-tech bodysuits.