J-League Data Lab — Transfer Case Files
Transfer Case Files
Short, structured records of individual J-League/K-League-to-Europe transfers, kept in step with our internal transfer-case dataset. No verdict — just the facts as logged, for later review.
Each case file follows one player's first move to a European club after a senior career in the J.League or K League. Players who went to Europe straight from a youth academy, school or university, with no senior league experience at home, are outside the scope. If a player signed for one club but first played for another, for example on a loan agreed at signing, the file records the club he actually played for.
Every case in our dataset carries one of four outcome labels:
- ESTABLISHED: became a regular first-team player at that club.
- DID_NOT_ESTABLISH: played little, then moved down a level or returned home.
- RETURNED_HOME: played regularly in Europe for a period but did not move up, and returned to Japan or Korea.
- TRACKING: less than a year since the move, so no outcome is assigned yet.
Labels judge the first European move only, not a whole career. This page lists 4 case files; the dataset behind them is larger and is updated as cases are reviewed.
Transfer Case File: Gaku Nawata, Gamba Osaka → Charleroi (loan with option)
A 20-year-old forward joins the Belgian Pro League on a loan with a purchase option. Three appearances and 59 minutes in, the senior sample is too small for a statistical verdict. Case status: Tracking.
Transfer Case File: Park Si-hu, Chungnam Asan (K League 2) → FC Arouca
Transfer Case File · KOR-008. An 18-year-old winger who became Chungnam Asan’s first player to move to Europe, signed by Arouca on a contract to June 2031. Corrected 2026-10-15.
Transfer Case File: Kyosuke Tagawa, FC Tokyo → Santa Clara → Heart of Midlothian
Transfer Case File · JPN-013. A two-stage European spell: a loan to Santa Clara that ended in relegation, a return to FC Tokyo, and a permanent move to Hearts 34 days later. Corrected 2026-10-15.
Transfer Case File: Shumpei Fukahori, Nagoya Grampus (J1) → Vitória SC
Transfer Case File · JPN-014. A six-month loan to Portugal at 20 that returned after four league appearances, and the long route back to proving he could score, which ran through J3. Corrected 2026-10-15.