Trailing Ledecky by nearly a body length at the halfway mark, Titmus launched a blistering final hundred to win the gold in 3:56.69, registering the second fastest time in history.

Whilst Canada's Summer McIntosh was third at the final turn, she faded down the stretch to finish fourth in a Canadian Record of 4:02.42.

China's Tang Muhan (4:04.10), Germany's Isabel Gose (4:04.98), the U.S. Paige Madden (4:06.81) and New Zealand's Erika Fairweather (4:08:81) rounded out the championship field, with all four swimmers slower than their preliminary times.

Up to two swimmers per National Olympic Committee (NOC) could automatically qualify by swimming that time at an approved qualification event.

Up to one swimmer per NOC meeting that time was eligible for selection, allocated by world ranking until the maximum quota for all swimming events was reached.