Brazil's Superior Tribunal of Sporting Justice (STJD) Friday confirmed relegation for Portuguesa for fielding a suspended player, thereby saving outgoing champions Fluminense from the drop.
In a tumultuous ending to the national league season, Fluminense looked to have become the first defending champions to be relegated the following season after finishing fourth bottom.
But the STJD upheld on appeal an initial decision to dock Portuguesa four points for fielding suspended midfielder Heverton in the Sao Paulo-based side's final match.
Another judgment Friday saw four-times champions Vasco da Gama fail to have their final-day defeat at Atletico Paraenense overturned -- a successful appeal would have kept them up at the expense of Rio neighbours Flamengo.
The match, which Vasco lost 5-1, was interrupted for more than an hour for crowd violence and the club insisted it should have been replayed.
The televised violence shocked the nation and led to a key Vasco sponsor, a Japanese carmaker, revoking its backing of the club while the Brazilian authorities called, not for the first time, for a tough crackdown on hooliganism.
Had Vasco won their case Flamengo would have been demoted after failing to recover four points docked for playing former Arsenal defender Andre Santos against Cruzeiro after earning a one-match ban in a cup match.
The four relegated teams were Nautico, Ponte Preta, Vasco and Portuguesa.
Portuguesa's Heverton had been slapped with a two-match ban for a sending-off in a previous game but came on for the last 13 minutes of a goalless draw with Gremio.
"The rules are made to be obeyed. Our ruling goes beyond Portuguesa or Fluminense -- these are rules governing football," concluded tribunal chairman Flavio Zveiter.
Portuguesa appealed the initial decision with chairman Manuel da Lupa alleging that had it been Fluminense in danger of the drop they would not have been punished so severely.
"For me, the matter doesn't end here. In football, you win on the pitch," Da Lupa said following Friday's ruling, indicating the club may take their case through the courts or even to the international Court of Arbitration for Sport.
One Brazilian sports commentator had, following the initial decision, decried the penalty as akin to "a life sentence for stealing a loaf of bread."
Portuguesa argued Heverton's suspension had not been published on the website of the Brazilian Football Confederation (CBF), of which the STJD is an offshoot, but the CBF said even had it been such notices are not official.
The club also claimed there had been a lack of communication between their legal officials and the club had not realised Heverton was not eligible to play in the final match.
The case has inflamed emotions just five months before Brazil host the World Cup and 150 police were on duty outside the hearing in Rio de Janeiro.