Atletico Madrid have proven that they have a pretty good mentality on the Champions League stage.
As the teams in the competition have reduced, the competition will now be tougher and by tomorrow being the 15th of March we will see the draws and the next teams to play each other going further into the competition. Atletico Madrid will be hoping to get teams like Dortmund, Arsenal, Barcelona, PSG who they know they can have a good chance against as they are almost on the same level. They would want to avoid Manchester City, Real Madrid that they know are very good and have an excellent record in the champions league.
You didn’t mention Bayern Munich amongst the team they may be scared to face in the quarterfinals alongside Manchester City and Real Madrid. They could pray to have a team like Arsenal and Dortmund but not. Barcelona and PSG whom they also have good records in the competition for long now also. I won’t underrate any of this teams too much when they’re faced with Atletico Madrid to play. They could get a more leniency when matchup with Dortmund or Arsenal, but for the rest of them, it will be as tough as hell for them to pass through into the semifinals. The next round of the competition will be entirely different and full of drama irrespective of any team any of the teams will be facing.