China's Olympic champion Sun Yang won his fourth consecutive world title in the men's 400m freestyle at the 18th World Championships on Sunday.

Sun finished first in the 400m free final, clocking three minutes and 42.44 seconds. It was his fourth straight gold medal of the FINA worlds in the event since 2013.

Mack Horton of Australia touched home as runner-up in 3:43.17. Italy's Gabriele Detti trailed with a time of 3:43.23 for the bronze.