Katie Ledecky showed it will take a monumental effort to pry the 800 metres freestyle title from her grip after the American great came home more than five seconds quicker that Summer McIntosh in the world championships heats on Friday.

Also Friday, Toronto’s Josh Liendo and Montreal’s Ilya Kharun booked spots in the men’s 100-metre butterfly final Saturday. The two shared the Olympic podium in Paris last year, with Liendo taking silver and Kharun the bronze. Liendo turned in the second-fastest time in the semifinals of 50.24 seconds, while Kharun was fourth in 50.39.

In Thursday’s edition of CBC Sports’ daily newsletter, we break down the most anticipated race of the swimming world championships: Summer McIntosh vs. Katie Ledecky in the 800-metre freestyle.