At the Toyota U.S. Championships, Olympic 200m breaststroke champion Kate Douglass narrowly defeated Lilly King, the 100m breast world record holder, in what marked King’s final domestic race. Douglass won by 23 hundredths of a second, qualifying both for the upcoming World Championships in Singapore, which will also be King’s last major international meet. In other events, Katie Ledecky claimed victory in the 400m free, Rex Maurer set a U.S. pool record in the men’s 400m free, and Regan Smith won the 100m backstroke, showcasing a day of notable performances.