A miserable run of results, not helped by a number of key injuries, has left Atleti's season in danger of derailing a little over a month into the new year.
Five games without a win, including a penalty shoot-out defeat to Real Madrid in the Supercopa de Espana final and a shock 2-1 Copa del Rey loss to Cultural Leonesa, has left Simeone's side with only LaLiga and the Champions League as potential trophies.
They are far from favourites for success in either competition, given they sit 13 points off leaders Madrid in the top flight and must face holders Liverpool in the last 16 in Europe.
Simeone, who now considers every remaining match to be a final, wants his players to show their mettle over what could be a decisive few weeks of their season.
"We have all finals," he told reporters on Friday. "We have a challenge and an important responsibility. We are going to compete with very good teams.
"We don't go beyond taking things game by game – we've always believed in that. I expect a full stadium, understanding the situation of the team, and the team understanding the situation of the championship. That's the most important thing."
When asked about Madrid and Barcelona's Copa exits this week, he added: "I'm very respectful of every team and I don't give an opinion on situations that don't involve us. I just think about improving and getting out of this dynamic, which isn't so good. We have to show that we are alive."
The good news for Atleti is that striker Diego Costa and midfielder Koke are close to returning.
A back problem has kept Costa sidelined since November, while Koke has only played once since December 14 due to hamstring issues.
Simeone hopes the comeback of a proven goalscorer and a creative midfielder can give his attack the lift they need.
"He's coming back. We'll see if he can play from the start," he said of Koke.
"Technically, he's a different footballer, he sees more than the others and we have more opportunities to create chances when he is on the pitch.
"Diego Costa has joined in with training this week. He's looking forward to coming back and the doctors will determine his all-clear when it's appropriate.
"It's important for the group [to have him back] and when he returns, we'll have a player who has always given us a lot."