"We face a very demanding match, but we have to perform at our level to get the win," the French midfielder said.
On the Champions League's importance: "This competition has changed a little, but we know we can play in the play-offs and aim to win it. If we take it step by step, we can finish among the top eight. The focus right now is tomorrow's game – we want to start the campaign on the right foot."
Tchouameni addressed the refereeing controversy from last Saturday's match: "Referees try their best every game. The most important thing is that we won. I don't have any complaints. Everyone saw what happened, and now we have to look forward."
Reflecting on Xabi Alonso's impact: "We've had great success under Carlo Ancelotti, one of the best managers in the world, but Xabi brings a different methodology. We've improved with him from the start of the season.
"Everyone feels good and is playing at their level. We hope to keep this momentum going."
On the pressure of playing for Real Madrid: "There's pressure here all the time. That's nothing new. Every season, we aim to win every title. Last year we didn't win much, so this season we're determined to achieve more."
Tchouameni also praised his compatriot Kylian Mbappe: "Kylian scored plenty last season and is continuing that form. As a team, we're stronger and have more options to win. He's playing at an incredible level, as he does every year."
Discussing tactical changes under Alonso: "We've made adjustments, some players have changed positions, and the methods are different. Marseille are a strong side with quality players, and we need to show our strength."
On Tuesday's opponents: "Marseille are a big club in Ligue 1. I expect a tough Champions League match. Many people in France follow them closely, and even friends have asked me for tickets. As a Frenchman and a Madrid player, I'm excited to face them."
Regarding Mbappe's Champions League ambitions: "We know he wants to win the Champions League – it's a club goal. Kylian always aims to win, and we'll work together as a team. First, though, we focus on tomorrow's match, both physically and mentally."
Finally, Tchouameni reflected on his milestone: "Playing 150 matches for Real Madrid is a dream. I want to enjoy every moment, play many more games, win titles, and make the most of each season here."