Cristiano Ronaldo sparked a storm of criticism on Monday for condemning the referee who awarded three penalties in Barcelona's dramatic win over Real Madrid.
Ronaldo said after the 4-3 Clasico defeat on Sunday night that referee Alberto Undiano Mallenco made "unbelievable" decisions and that unnamed forces wanted Barcelona in the title race.
Barcelona players said the comments by the world player of the year were unjustified. Sport newspaper called Ronaldo a "cry baby".
Lionel Messi scored three goals, two from penalties, in one of the most dramatic matches between the arch-rivals. The result took Barcelona just one point behind Real and Atletico Madrid at the top of the Spanish table.
Mallenco gave Madrid defender Sergio Ramos the 19th red card of his career and Ronaldo, who scored from a controversial penalty himself, blasted the referee.
"The decisions that the referee took, for me it was unbelievable," the Portuguese striker said.
"It makes you think that maybe they don't want Madrid to win this league. Or they don't want to completely rule out Barca, because if Barca had lost today they would have been dead."
"There were a lot of mistakes for just one game. A match between Real and Barca ought to have a high level of referee," added Ronaldo.
"You can't make correct decisions when you are nervous. It makes me think that it is not just on the field that you win games, a little help from outside helps too.
"My penalty might have been just outside the area, but there are many things that went on. It is difficult when many people didn't want us to win today."
Barcelona's Xavi Hernandez said Ronaldo had "spoken too soon" and that the referee had been "fair". Gerard Pique also called on Ronaldo to stop "complaining".
Marca newspaper commentator Roberto Palomar said Ronaldo "ended up spewing stupidities in the press room. He can be forgiven for being who he is."
"As usual when they lose, Real Madrid's worst image returned," said Barcelona newspaper Sport. Ronaldo's criticism "showed once again that, when things don't go the way he wants, the arrogant, ill-humoured Cristiano reappears."
Barcelona players put out a storm of Twitter comments and triumphant photos after the match that the Spanish press hailed as one of the best Clasicos ever, particularly as it left Spanish title race wide open.
Messi's hat-trick made him the most prolific scorer in the history of matches between the arch rivals.
"Barcelona emerged the victors in all aspects of a frenetic night of football and goals, one of the best duels that the eternal rivalry between the two giants of the Liga has produced," wrote Marca.
Real Madrid did everything they could to win but Barcelona had the answer, the paper said.
"Driven by the sensational Iniesta and held by the genius of Messi, Barca overcame every adversity," Marca said.
Real Madrid's defeat left them trailing Spanish league leaders Atletico Madrid on goal difference, with Barcelona just one point behind.
Despite the acrimony, Ronaldo insisted that Madrid had to forget the defeat and was determined to fight for the title.
"We have to look forward to the next games. Wednesday we have an important game against Sevilla and we have to win. We are one point in front of them and we have to fight until the end," said the striker.
Madrid coach Carlo Ancelotti demanded an immediate response from his side against in-form Sevilla.
"Obviously we are not happy because we have lost a big opportunity, but we will continue fighting until the end," he said.
"There are nine games left and it will be an intense race. The league is open for all three teams and any game could be decisive. We need a good reaction on Wednesday because that could be the key game of the season."