China's Li Bingjie broke the Asian record and claimed the Olympic 400m freestyle bronze medal in a hard-fought contest.
The 19-year-old hit the wall in 4:01.08, with Australian swimmer Ariarne Titmus clinching the gold in 3:56.69. American veteran Katie Ledecky failed to recapture her top form in Tokyo as the world record holder finished second in 3:57.36.