TOKYO — For nearly a decade, Katie Ledecky has lived a mostly blessed athletic existence.
As a painfully shy 15-year-old, she upset a defending gold medalist and world-record holder to win her first Olympic title at the 2012 London Games. She has had barely a slip since.
Her domination is so routine that her surname has become a verb, synonymous with crushing the competition. And she has ledeckied away in her specialties — distance swims longer than 400 meters — rarely facing a true challenger and certainly nothing resembling a rival.
Now, she has one.
Ariarne Titmus of Australia, a fearless Tasmanian who talks big and has the speed in the pool to back it up, is about to ask Ledecky the one question she has never had to answer in her two previous Olympic appearances: How will she respond to a swimmer who has placed a target on her back and taken dead aim at it?