Leon Marchand sliced a mighty 5.32secs from his national 400IM record in 4:09.65 at the French Olympic Trials in Chartres.
The 19-year-old set the previous mark of 4:14.97 at the FFN Golden Tour in Marseille where he booked a trip to Tokyo in the 200IM.
Splits: 56.74; 2:02.90 (1:06.16); 3:11.84 (1:08.94) 4:09.65 (57.81)
Marchand will continue a family Olympic tradition when he competes in the Japanese capital.
His father, Xavier, represented France at the 1996 Games in Atlanta and four years later in Sydney in a career that brought world and European 200IM medals and mother, Celine Bonnet, competed at Barcelona in 1992.
The best of the rest was Emilien Mattenet who was almost eight seconds adrift on 4:17.50 with Jaouad Syoud of Algeria third in 4:19.02.
Cyrielle Duhamel (2:11.47) and Fantine Lesaffre (2:12.47) also booked tickets to Japan in the 200IM.
Sweden’s Louise Hansson won the 100 fly in 57.05 ahead of Marie Wattel (57.37) and Beryl Gasteldello (58.33), the latter having yet to seal qualification with her eyes on the 100 free on Saturday.
Tunisian Ayoub Hafnauoi won the 400 free in 3:46.16 ahead of Joris Bouchaut (3:47.37) and open water specialists Logan Fontaine and Marc-Antoine Olivier, on 3:48.75 and 3:49.26 respectively.
Theo Bussiere won the men’s 100 breaststroke in 1:00.25 ahead of Antoine Viquerat (1:00.49) and Carl Aitkaci (1:01.13).
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