Katie Ledecky stunned by Ariarne Titmus in 400-meter freestyle at worlds

GWANGJU, South Korea — Bethesda's Katie Ledecky is usually there in the end, her endurance powering her to the wall well ahead of the competition.

Someone else got there first at the world championships on Sunday night.

Ariarne Titmus of Australia chased down Ledecky over the last lap to win ...