He has represented both Germany and Turkey internationally at youth level.
Club career
Early career
Arslan was born and raised in Germany, in Paderborn, to Turkish parents from Çorum; his father Erhan Arslan, a real estate agent, moved to Germany when he was 11 years old. He began playing football at the age of six, when his father brought him along to watch Grün-Weiß Paderborn play. Arslan began his career with the local club. Patterning his game around Zinedine Zidane and Gheorghe Hagi, Arslan earned a move to Borussia Dortmund in 2003. After several years in Dortmund's youth team, Arslan moved to Hamburger SV.[2]
Hamburger SV
Arslan moved to Hamburger SV on a free transfer in 2009. He made his debut on 23 September 2009, coming in the 70th minute as a substitute for Marcus Berg in the second round of the DFB-Pokal against Osnabrück.[3] Hamburg managed a 3–3 draw, but went on to lose 5–7 following a penalty shootout. Arslan made his league debut on 17 October 2009 in a 0–0 draw against Bayer Leverkusen.[4]
On 27 January 2015, Arslan signed a four-and-a-half-year deal with Süper Lig club Beşiktaş.[6] He came on as a substitute for José Sosa on 26 February in the 60th minute of a UEFA Europa League last 32 second leg against Liverpool, and 15 minutes later scored the only goal of the game, taking it to a penalty shootout in which he scored Beşiktaş' last attempt before Dejan Lovren missed to eliminate Liverpool.[7]
Fenerbahçe and Udinese
In January 2019 he moved to Fenerbahçe where he will play until June 2020 and then change league by going to Italy for three seasons for Udinese.
Melbourne City
On 15 June 2023, his move to Australia was announced, signing a two-year contract with Melbourne City. He made his debut in the Australia Cup against Oakleigh Cannons, in which he scored two penalties in a 3–2 win. His goalscoring run would continue for the next two rounds of the 2023 Australia Cup, with a deflection goal credited to Arslan coming from a shot from Steven Ugarkovic against Wellington Phoenix and a penalty rebound against the North Eastern MetroStars. his departure from the club was then announced on 9 July 2024.[8]
Sanfrecce Hiroshima
On 21 July 2024 it was announced that Tolgay had signed for J1 League side Sanfrecce Hiroshima.[9] On 11 August 2024, he scored his first goal for the club against Cerezo Osaka also achieving a brace.[10] On 31 August 2024, he scored a hat-trick in a 3–2 victory over FC Tokyo.[11]