[1] As the most decorated Olympian of all-time, Michael Phelps got the opportunity to avenge the distance butterfly title that he lost in London four years earlier, when South Africa's Chad le Clos beat him to the wall.

[2] Moving to the front at the halfway turn, Phelps held off the Japanese challenger Masato Sakai by a 0.04-second margin to claim his twentieth Olympic gold medal and twenty-fifth overall in 1:53.36.

[3][4][5] Coming from sixth at the 150-metre turn, Sakai made a late surge on the final length to nearly upset Phelps towards a close finish, but he ended up taking the silver in 1:53.40.

[7][8] Le Clos did not produce another striking effort to halt the most decorated Olympian from snatching the title, as he was shut out of the medals to fourth in 1:54.06.

[6] Hungarian swimmer, 2008 Olympic silver medalist, and reigning world champion László Cseh commanded a brief lead on the initial length, but faded shortly to seventh place in 1:56.24.