FC Augsburg Thommy joined
FC Augsburg in 2010 from
TSG Thannhausen and
SSV Ulm 1846. At 16 February 2014, he made his
Bundesliga debut in a 0–1 home defeat against
1. FC Nürnberg. He appeared as an 82nd-minute substitute.
Kaiserslautern (loan) In January 2015, Thommy was loaned to
2. Bundesliga club
1. FC Kaiserslautern for a year and a half until summer 2016. However, at the occasion of announcing his loan,
FC Augsburg's general manager
Stefan Reuter stated that Thommy still was a component of their future plans. Thommy was contracted with Augsburg until 2018. The loan was ended on 31 January 2016.
Jahn Regensburg (loan) In the 2016 summer transfer window, he was loaned out again, this time to
SSV Jahn Regensburg. He made his league debut and first start for
Regensburg on 30 July 2016 in a 2–0 home victory over
F.C. Hansa Rostock. He was subbed off in the 82nd minute, being replaced by
Uwe Hesse.
Stuttgart On 18 January 2018, Thommy moved to
VfB Stuttgart. His debut and first competitive start for
Stuttgart came on 3 February 2018 in a 1–1 away draw against
VfL Wolfsburg. He scored his first Bundesliga goal on 24 February 2018 against Eintracht Frankfurt. On 19 August 2018, Thommy extended his contract with VfB Stuttgart until June 2022. On 28 May 2022, Stuttgart announced that they would not extend Thommy's contract beyond the
2021-22 Bundesliga season.
Düsseldorf (loan) On 10 July 2019,
Fortuna Düsseldorf announced the signing of Thommy on loan until the end of 2019–20 season with an option to buy him permanently.
Sporting Kansas City On 23 June 2022, it was announced that Thommy had signed with
Major League Soccer side
Sporting Kansas City on a deal until the end of the 2024 season. Thommy debuted for Kansas City on 23 July 2022, starting in a 0-2 loss to
Los Angeles FC. Following the 2025 season, Kansas City opted to release him from the club. ==Career statistics==