As is customary, the sporting action at this summer's Olympic Games will actually begin before the opening ceremony on Friday (5 August). The eagerly-awaited football competition starts early to accommodate all of the group games, meaning the first Olympians in action will be the South African and Swedish women's teams.
Where to watch
The BBC is showing live coverage of South Africa versus Sweden via their website from 16:45 BST, while updates of the opening game are also available via BBC Radio 5.
The events to watch
In addition to the opening football match of the Olympics from the Joao Havelange Olympic Stadium in Rio, the first day of competition will see Brazil's women play against China at the same venue. Elsewhere, defending champions the United States are poised to face New Zealand in Belo Horizonte at 23:00 BST.
Other matches on the opening day include Canada versus Australia, as well as Zimbabwe versus Germany.
Brit to watch
As Great Britain do not play football at the Olympics, because the home nations cannot agree on how to combine, no British athletes will be in action on the opening day. In fact, the London Olympics was the only time they have entered a football team since 1960.
- Sweden vs South Africa (17:00 BST)
- Canada vs Australia (19:00 BST)
- Brazil vs China (20:00 BST)
- Zimbabwe vs Germany (22:00 BST)
- United States vs New Zealand (23:00 BST)