After a spell at RFC Union Luxembourg (2012 to 2015), Leandro Barreiro returned to his original club (2015/16) before making a permanent move to Germany. The midfielder joined the FSV Mainz 05 academy at the start of the 2016/17 season.
An international for Luxembourg since the U16 level, Barreiro completed his entire youth development at the German club, where he made his professional debut. On February 8, 2019, in a home match against Bayer Leverkusen (1-5), he played his first minutes for the FSV Mainz 05 first team.
His performances, competitive attitude, and intensity in the midfield during the 2019/20 season gradually earned him a place in the team, as he participated in 18 matches.
In the 2020/21 season, he solidified his position in the first team, and over four seasons (2020/21 to 2023/24), he remained a key player for FSV Mainz 05, accumulating a total of 132 matches and 11 goals across all competitions played by the German team during that period.
At the same time, Barreiro – who earned 16 caps and scored two goals between the U16 and U21 levels – became one of the key figures in Luxembourg’s senior national team, a country he had represented nearly 60 times at the time of his move to Benfica. His debut took place on March 22, 2018, in a friendly match against Malta.
