Barcelona's Dani Alves protested his innocence over the penalty decision which allowed 10-man Real Madrid to salvage a draw at the Bernabeu.
Barca looked to be heading for a record-equalling sixth successive 'Clasico' victory over Madrid as they led heading into the final 10 minutes against a home side that played almost the entire second half with a man less following Raul Albiol's red card.
However, Madrid were given a lifeline when Marcelo went crashing over Alves' challenge inside the area, earning the home side a penalty which Cristiano Ronaldo coolly slotted in to level the game up at 1-1.
Alves felt the referee had got it wrong though, saying: "I don't agree with the referee's decision because I got the ball cleanly and didn't touch him (Marcelo)."
His team-mate Seydou Keita, whose side also felt they should have been awarded a penalty themselves in the first half when David Villa appeared to be brought down by Iker Casillas, added: "It wasn't a penalty. He (Alves) got the ball and it was never a foul. We don't like to talk about the referees and it's better to focus on the next matches."
Despite Madrid's late equaliser, Barca further strengthen their hold on the Primera Division title race with the draw, as they are now eight points clear with only six games to go and also have the better head-to-head record.
Alves added: "It's positive that they didn't beat us. We have to continue along this line, picking up points and trying to keep our advantage until the end. We are in the same position, but now with a game less."
Last night's clash was the first of four meetings between the two arch rivals in the space of 18 days, with the next coming up in just four days time when they meet in the final of the Copa del Rey.
"We have to continue like that because on Wednesday we have a massively important game. Let's see if we have more luck," added Alves on his club's website.
"We are very motivated for the cup, especially after this game. We deserved more and football always offers you a new opportunity and that will be on Wednesday."