Lukas Manuel Klostermann (German pronunciation: ; born 3 June 1996) is a German footballer who plays as a defender for RB Leipzig.
Born in Herdecke, Germany, Klostermann played for various youth teams at FSV Gevelsberg, SSV Hagen and VfL Bochum. While at FSV Gevelsberg, he played in various position before settling in playing defensive position at VfL Bochum.
After progressing through VfL Bochum’s youth system, Klostermann was promoted to the U19 side and then VfL Bochum II. At some point, he signed a contract with the club, keeping him until 2015. He made his debut for the club, coming on as a second–half substitute, in a 2–0 win over VfR Aalen on 14 March 2014. At the time of his debut, he appeared at just 17 years and 283 days. Towards the end of the 2013–14 season, Klostermann pushed Paul Freier out of the first team over a right–back position. His handful of first team appearances resulted him being named the club’s Player of the Month for May. At the end of the 2013–14 season, he made nine appearances for the side.