French hero Leon Marchand threw down the gauntlet with a storming 400m medley swim Sunday as Mollie O'Callaghan outgunned Ariarne Titmus to top the women's 200m freestyle heats. Marchand is the Olympic hosts' big hope after last year demolishing Michael Phelps' 15-year-old world record in a phenomenal 4min 2.50sec. The 22-year-old, trained by Phelps' old coach Bob Bowman, had not dipped under 4:10 this year as a number of his rivals did, piling on the pressure. FRANCE 24's Selina Sykes reports.
