Swim Showdown: US Star Ledecky, Aussie to Battle for Gold

Katie Ledecky, of the United States, reacts following her heat of the women's 400-meter freestyle at the 2020 Summer Olympics in Tokyo, Japan, on July 25, 2021. Matthias Schrader/AP

TOKYO—Katie Ledecky’s teammates are already piling up Olympic medals. Now it’s her turn, and she wants some hardware of her own.

Ledecky opened her Olympic program as the top qualifier in the 400-meter freestyle on Sunday night, setting up a showdown with Ariarne Titmus of Australia as the American star tries to defend her title.