Speaking ahead of Tuesday night's clash at the Metropolitano, Simeone insisted his side were ready to finish the job after taking a two-goal advantage from the first leg.
"We are clear on what is required and what we aim to achieve," Simeone said. "Our objective is to progress, and we will play to ensure that happens."
Atletico have built a reputation for resilience under Simeone, particularly in high-pressure European ties, and the Argentine underlined that nothing would change in their approach despite the stakes.
"We have been competing at this level against them for a long time," he added. "We know the calibre of the side we are facing, but our mission remains the same - we must progress."
The build-up to the match included discussion around referee Clement Turpin, but Simeone dismissed any concerns, choosing instead to back his team.
"My focus is on the team, not the referee," he said. "He has a massive and difficult job. The closer you get to a final, the more pressure there is, but honestly, it's not something I'm thinking about."
Reflecting on the first leg, Simeone pointed to Atletico's early control as a key positive.
"We moved the ball well in the opening 20 minutes and controlled more of the game in their half than expected," he explained. "We have faith and total confidence in our plan."
In defence, injuries have forced changes, with Robin Le Normand and Clement Lenglet expected to start.
"Robin is improving with every game, and Clement brings great experience," Simeone said. "They know exactly what is expected, and we will use their strengths for the team."
With a semi-final place on the line, Simeone's message was simple: stay focused, trust the system, and finish the job.