Adriano, who has revived his career at home in Brazil since leaving Inter Milan in April, took his leading scorer's tally to 15 at the Maracana, where 78,409 fans set a Brazilian championship record for the season.
"The Emperor" scored twice in 12 minutes early in the second half to lift Flamengo, unbeaten in six matches, into sixth place and push their "Fla-Flu" derby rivals deeper into relegation danger.
Fluminense forward Alan was taken from the pitch in an ambulance in the second half after a clash with Flamengo defender David but the club later said he was not seriously hurt.
Palmeiras coach Muricy Ramalho, whose side are five points clear with 53 points after 27 matches, is dreaming of a fourth successive Brazilian title having steered Sao Paulo to the championship in the last three years.
"We don't have a super team but we have very determined athletes who never give up," Ramalho told reporters after Palmeiras came from a goal down for the win. "It's very pleasing to work with a squad like that."
MINEIRO UP
Sao Paulo are second with 48 points after their 2-1 win at Nautico on Saturday, while Atletico Mineiro climbed to third a point behind them with a 2-1 home win over Barueri.
Brazil striker Diego Tardelli scored Mineiro's opener to take his goal tally to 14, one less than Adriano, while their Uruguayan goalkeeper Fabian Carini saved a penalty from Basilio after he had brought the striker down.
Barueri had defender Xandao sent off with nine minutes to go for a foul on Tardelli, his second yellow card offence.
Goias dropped to fourth on 45 points after a 3-1 home defeat by lowly Botafogo, while Internacional are now fifth following a 2-0 defeat away to Coritiba.
Ronaldo's Corinthians were beaten 3-1 at home by Atletico Paranaense and are now 10th, having failed to win their last four matches.
Argentine striker Maxi Lopez scored twice as seventh-placed Gremio were held 3-3 at home by Sport Recife.
