2021 Campeonato Carioca
The 2021 Campeonato Carioca de Futebol was the 118th edition of the top division of football in the state of Rio de Janeiro. The competition is organized by FERJ. It began on 16 January 2021 and ended on 22 May 2021. The tournament was played behind closed doors due to the coronavirus pandemic in Brazil. In order to lower the number of matches to be played, this edition of the Campeonato Carioca faced another change in format and regulations. Flamengo, the defending champions, won a record-breaking 37th Campeonato Carioca title and their third title in a row.
Participating teams
| Club | Home City | Manager | 2020 Result |
| Mesquita | Álvaro Gaia and Josué Teixeira | ||
| Cardoso Moreira | Caé Cunha | ||
| Rio de Janeiro | Marcelo Marelli | ||
| Saquarema | Leandrão | ||
| Rio de Janeiro | Marcelo Chamusca | ||
| Cabo Frio | Rogério Corrêa | ||
| Rio de Janeiro | Rogério Ceni | ||
| Rio de Janeiro | Roger Machado | ||
| Nova Friburgo | Cadão | ||
| Macaé | Eduardo Allax, Charles de Almeida, Dário Lourenço and Luciano Lamóglia | ||
| Rio de Janeiro | Toninho Andrade and Alfredo Sampaio | ||
| Nova Iguaçu | Carlos Vitor | ||
| Rio de Janeiro | Felipe Surian | ||
| Resende | Sandro Sargentim | ||
| Saquarema | Flávio Tinoco | ||
| Rio de Janeiro | Marcelo Cabo | ||
| Volta Redonda | Neto Colucci |
Format
The competition format went through a series of alterations in order to minimize the number of matches to be played. The relegation play-offs, Taça Independência and Torneio Extra were scrapped, and the main phase was played in a single round-robin, instead of a double round-robin.Preliminary stage
The preliminary stage of the tournament was contested as a double round-robin among the four worst-placed teams of the 2020 Campeonato Carioca and the two teams promoted from the 2020 Série B1. The winner of the preliminary stage qualified for the main phase of the competition while the remaining five were relegated to the 2021 Série A2.Main stage
In the main competition, the twelve clubs played each other in a single round-robin called the Taça Guanabara. The last placed club was relegated to the 2021 Série A2. The top four clubs qualified for the final stage while the next four clubs qualified for the Taça Rio. In the Taça Rio, the 5th-placed club faced the 8th-placed club, and the 6th-placed club faced the 7th-placed club. In the final stage, the winner of the Taça Guanabara faced the 4th-placed club, while the runners-up faced the 3rd-placed club. In both of these four-team brackets, the semifinals and finals were played over two legs, without the use of the away goals rule. In the semifinals of both the Taça Rio and the final stage, the better placed teams in the Taça Guanabara table advanced in case of an aggregate tie. In the finals of both brackets, there was no such advantage; in case of an aggregate tie, a penalty shoot-out would take place.The top three teams of the Campeonato Carioca and the winner of the Taça Rio qualified for the 2022 Copa do Brasil. Since Botafogo also qualified for the 2022 Copa do Brasil via winning the 2021 national Série B, and Flamengo and Fluminense qualified for the 2022 Copa do Brasil via the 2021 national Série A, their Campeonato Carioca berths went to the next best team. The top two teams of the Campeonato Carioca that were not already playing in the Campeonato Brasileiro Série A, Série B or Série C qualified for the 2022 Série D.