Swimming kicked off day one of the Olympic Games in fine fashion, complete with several jaw-dropping moments, come from behind wins, disappointments and the first of two matchups between Ryan Lochte and Michael Phelps.
The day began with numerous preliminary heats.
Once the tables were set, it was on to the finals in the men's 400-meter freestyle, women's 4x100-meter freestyle relay, and both men's and women's 400-meter individual medley.
July 28 saw 28 heats, four semifinals and four finals competitions.
Here are the highlights from all 36 races.