Career
Langer made his Association of Tennis Professionals main draw debut at the 2009 International German Open in the doubles event where he partnered Kevin Krawietz, but lost in the first round to Marcelo Melo and Filip Polášek, 0–6, 4–6. At the 2013 MercedesCup he qualified for the tournament, defeating Ivo Klec, January Mertl and Evgeny Korolev in the qualifying rounds. In the main draw he drew fellow compatriot Robin Kern, a wildcard entrant, winning 3–6, 6–4, 6–3.
His run came to an end where he lost to the second seed and fellow compatriot Philipp Kohlschreiber, 5–7, 2–6.
Doubles (1).