Summer McIntosh's goal at the world championships was 5 gold in 5 races, but it was not to be for the 18-year-old phenom. American Katie Ledecky & Australia's Lani Pallister stood in her way in the 800 freestyle final.

Katie Ledecky has dominated the women's 800m freestyle for over a decade, but Canadian Summer McIntosh is on her tail, setting up a massive showdown.