Adrian Lopez says Atletico Madrid are prepared to show their nasty streak in a bid to beat Real Madrid on Saturday evening.
Los Rojiblancos have not beaten Jose Mourinho's side since 1999 but find themselves eight points clear of their city rivals in the Liga table ahead of the game.
As a result, the forward is expecting a fierce encounter to ensue and says he and his team-mates must stick together if they are to take anything away from the Santiago Bernabeu.
"They have lost points which is not normal for them, but the derby is also very important to [Real] Madrid," he told As.com
"They will go all out from the start. It is important that we put up with the first few minutes and stand firm. If they come to bite us in the derby then we need to do the same.
"It's at home and I know that playing at the Bernabeu is very complicated and they are a great team. We will try to play our game and be our best."
Diego Simeone's side sit in second place in the division with 34 points from their opening 13 games, three behind leaders Barcelona.