Atletico Madrid full-back Filipe Luis believes the key to their success this campaign has been the positive atmosphere in the dressing room.
Diego Simeone's men find themselves second in La Liga having started the season with 11 wins from 13 matches.
The 27-year-old has put the impressive displays down to the camaraderie among the players and the willingness to work hard as a team.
"There are no divides in the dressing room and it shows because every time we play, we come out fighting and wanting to help each other out," Filipe told reporters.
"Even the players that are not playing get fully behind the team – that is what makes us a winning team like we were last year.
"What we are doing this year is all connected to the fact that we work as a unit."
Ahead of the Madrid derby, the Brazilian said his team will focus on their game plan rather than trying to counter threats posed by their opponents.
"Madrid are Madrid. We are the Atleti, we will think about our game plan in the match and the rest will take care of itself," he said.