Zárate, 17, posted a time of 1min 14.72sec at the Olympic Aquatics Stadium to better the 1:15.62 he set in Mexican city Mérida last November.

Second-placed Tomotaro Nakamura of Japan was nearly 10 seconds behind in 1:24.58, while the United States' Rudy Garcia-Tolson came third in 1:25.30.

Brazilian swimmers continued to shine today, claiming five gold medals to add to the six they won yesterday.

Carlos Farrenberg set the hosts on their way to another impressive haul by winning the men’s 50m freestyle S13 in a time of 24.89sec. 

Russia’s Aleksandr Golintovskii came second in 25.21 and another Brazilian, Guilherme Batista Silva, was third in 26.00.

Home favourite André Brasil followed up his two victories yesterday by taking top honours in the men’s 100m backstroke S10 and the men’s 400m freestyle S10.

Brasil clocked a time of 4:14.27 in the freestyle to finish ahead of compatriot Gabriel Alves Tomelin, the runner-up in 4:25.97, and Sweden’s Ludvig Nyrén, the bronze medallist in 4:31.97.

In the backstroke, the 31-year-old touched home in 1:01.76 as Argentina’s Amilcar Guerra took silver in 1:08.21 and Nyrén came third in 1:13.94.

The evening session saw two young Brazilian swimmers strike gold with 17-year-old Cecília Jerônimo and 23-year-old Caio Amorim winning the women’s 50m freestyle S8 and men’s 400m freestyle S8 respectively.

Jerônimo posted a time of 31.83 to stand atop a podium which also featured the United States’ Mallory Weggemann and McKenzie Coan, second and third in 32.25 and 33.88.

Amorim also fended off an American challenge, winning with a time of 4:38.24 to stave off Robert Griswold in 4:53.58.

Today's world record-breaker Zárate completed the top three after touching home in 5:02.57.

Action in Rio de Janeiro is set to conclude tomorrow.