Coritiba broke Flamengo's six-game winning run on Thursday with a 2-0 victory in Brazil's Serie A championship.
Kleber Gladiador opened the scoring at the Maracana stadium before Henrique Almeida added another before the half-hour mark, Xinhua news agency reported.
The result saw Flamengo drop to fifth in the standings with 41 points, 13 points behind leaders Corinthians. Coritiba rose to 15th with 30 points.
In Thursday's only other match, Chapecoense held hosts Sao Paulo to a 0-0 draw at the Morumbi stadium.
Sao Paulo remain fourth in the standings while Chapecoense rose to 13th.