Ledecky clocks her fastest 400m free since 2018 in Mission Viejo
The five-time Olympic champion broke the four minutes in the event to take her second win in as many days at the 2021 TYR Pro Swim Series.
The American clocked 3:59.25 on Saturday 10 April to win her second event in as many days during the third day of the 2021 TYR Pro Swim Series in Mission Viejo, California.
Her time was over seven seconds faster than second-placed Leah Smith, the Rio 2016 bronze medallist, who swam a season best 4:06.37.
On Friday Ledecky recorded her second-fastest time ever in the 200m free.
The reigning 400m Olympic champion has broken the four-minute barrier for the 20th time in her career to record her best time since August 2018, the 15th fastest performance in history over the distance.
"That one didn't feel as good as some of my other swim this week," the 24-year-old told NBC Sports despite her best performance in a pre-May meet.
"But I am happy with my time."
In the other finals of the day, Bruno Fratus claimed the men's 50m freestyle in 21.80, edging reigning world champion Caeleb Dressel by just 0.03 seconds.