Leandro Barreiro's journey in the UEFA Champions League reached new heights this season, as he became the first Luxembourg player to compete in the tournament's knockout stage.

Leandro Barreiro has become the fourth player from Luxembourg's national men's football team to play in the UEFA Champions League, following his transfer from Mainz 05 to S.L. Benfica. Notably, he is the first Luxembourg player to advance to the tournament's knockout rounds.

Barreiro and Benfica faced FC Barcelona in the round of 16, following a narrow 0-1 defeat in the home leg, in which he featured for 70 minutes. The return match at Barcelona's Olympic Stadium on Montjuïc proved challenging, with the 25-year-old Luxembourg international starting on the bench. He watched as 17-year-old Lamine Yamal shone, assisting the first goal and scoring a stunning second to make it 2-1. By the time Barreiro was substituted on in the 70th minute, Benfica trailed 3-1, effectively ending their Champions League campaign.

Despite the elimination, Barreiro described the experience as something special. "The Champions League is every player's dream, I think", he said in a post-match interview. When asked what advice he would give a child from a small village in Luxembourg watching him play and wanting to follow in his footsteps, he emphasised the importance of self-belief, hard work, and resilience. "There will be tough moments, but you have to get through them and always keep a clear goal in mind", he advised young aspiring players. He also stressed the value of focusing on personal growth and listening to those who genuinely want to help, such as coaches and mentors, while acknowledging that luck also plays a role in success.

When asked about his post-match analysis, Barreiro admitted it was difficult to assess the game immediately after the final whistle. He praised Benfica's effort but acknowledged the team's struggles against Barcelona's offensive and defensive prowess. Regarding his own performance, Barreiro noted his limited playing time and the challenging circumstances when he entered the match.

On the experience of watching from the sidelines, Barreiro stated the importance of being ready to contribute whenever called upon. "As a player, you have to accept that sometimes you play from the start and sometimes you don't", he said, adding: "the key is to help your team when you're on the pitch".