Paris Olympics swimming: Katie Ledecky back in the swing after 400m freestyle setback

Katie Ledecky bounces back in Paris Olympics, while Leon Marchand impresses in the pool, setting the stage for thrilling finals.

Katie Ledecky shrugged off her disappointing 400 metres freestyle bronze to top qualifying for the 1,500m final at the Paris Olympics on July 30 as Leon Marchand mania returned to a buzzing La Defense Arena.

Three days after coming a distant third behind Australian champion Ariarne Titmus and runner-up Summer McIntosh in the 400m, seven-times Olympic gold medallist Ledecky was fastest in the 1,500m heats in 15 minutes 47.43 seconds.

The time was nearly four seconds better than the second quickest swimmer, Italian Simona Quadarella, who was runner-up to Ledecky at last year's World Championships in Fukuoka.

World record holder Ledecky won the inaugural women's 1,500m at Tokyo three years ago and it would take a huge upset for her to miss out on another gold in the event in Paris.

Victory would see her match fellow American Jane Thompson's all-time record of eight gold medals in Olympic women's swimming, with still the 800m freestyle to come.

"Had a good two days off. Was excited to get back into racing today," Ledecky told reporters.

Home hope Marchand returned to the pool two days after being feted like a rock star by the Parisian crowd for blitzing the field for gold in the 400m individual medley.