In July 2011, Inui made the jump to Europe, joining Germany'sVfL Bochum.[4] He made his debut in the2. Bundesliga, when he started in a 2–1 home defeat versusFC St. Pauli on 13 August 2011.
In July 2012, Inui signed a three-year contract with newly promotedBundesliga clubEintracht Frankfurt after impressive performance in the 2. Bundesliga.[5]
On 26 August 2015, Inui was transferred toLa Liga sideSD Eibar for a then club record fees of€ 300,000, after agreeing to a three-year contract.[6][7] He became the first Asian player to play for the club. On moving to Eibar, Inui said, “It was always my dream to play in the Spanish league one day. It’s been my dream since I was a child and now it’s come true”.[8]
Takashi made his debut for Eibar on 23 September 2015, starting and providing one assist in a 2–2 draw againstLevante. He scored his first league goal for Eibar on 10 January 2016 in a 2–1 win againstRCD Espanyol, scoring the first goal in the 15th minute of game and also providing assist for second goal.
In April 2017, as the club was chasing aUEFA Europa League place, he was controversially called back to his homeland by Japan's prime minister to serve as a delegate for the visit of KingFelipe VI of Spain to Japan.[9] On 21 May 2017, Inui became the first Japanese footballer to score againstFC Barcelona, sniping the ball via cross-bar behindTer Stegen, twice.[10]
On 1 June 2018, upon expiration of his Eibar contract, Inui joinedReal Betis on a free transfer for a three-year deal.[11] He made his debut forBetis on 17 August 2018, coming on as a substitute forWilliam Carvalho for the last 25 minutes in 3–0 loss againstLevante.
The following 24 January, after being sparingly used, he moved to fellow leagueDeportivo Alavés on loan until the end of the season.[12] He made his debut for Alavés on 11 January 2019 in a 2–0 winLevante. He scored his first goal for Alavés on 2 March 2019 in a 2–1 victory againstVillarreal.
On 22 July 2022, Shimizu S-Pulse announced that they have signed Inui after his contract with Cerezo Osaka was terminated.[15] On 27 October 2024, Inui was brought his club secure promotion toJ1 League from next season after win at away game againstTochigi SC 1-2 in matchweek 36. Seven days later at same year, Inui was brought his club secure champions of J2 in 2024 season after defeatIwaki FC with narrowly score 1-0 in matchweek 37.
Inui made his full international debut for Japan on 20 January 2009 in a2011 AFC Asian Cup qualification againstYemen.[16] In May 2018 he was named in Japan's preliminarysquad for the2018 World Cup inRussia.[17] On 24 June, Inui scored his firstWorld Cup goal in a 2–2 draw overSenegal during their second group stage match of the tournament. Inui went on to score another goal and registered an assist in the tournament.[18]
