Has there ever been a 5–4 in the Brasileirão?

Yes, 10 times.

The first time: February 15, 1978, Cruzeiro beat Fast Clube (Cruzeiro 5–4 Fast Clube).

The last time: May 5, 2019, Fluminense beat Grêmio (Grêmio 4–5 Fluminense), 7 years ago.

Home wins: 6. Away wins: 4.

Nearby scores

1. 6–3 7 times
2. 6–4 5 times
3. 6–5 Never
4. 5–3 37 times
5. 5–4 10 times
6. 5–5 2 times
7. 4–3 111 times
8. 4–4 17 times

All games

1. May 5, 2019 Grêmio 4–5 Fluminense
2. November 16, 2011 Fluminense 5–4 Grêmio
3. July 27, 2011 Santos 4–5 Flamengo
4. August 6, 2005 Atlético-PR 5–4 Cruzeiro
5. November 4, 2001 Portuguesa 5–4 Vasco da Gama
6. August 13, 2000 Goiás 4–5 Vitória
7. November 14, 1999 Vitória 5–4 Vasco da Gama
8. September 19, 1998 Ponte Preta 4–5 Corinthians
9. April 10, 1985 Paysandu 5–4 Sampaio Corrêa
10. February 15, 1978 Cruzeiro 5–4 Fast Clube