Attacking · Kashiwa Reysol · season-by-season, by competition, and every match.
A career still climbing — Koyamatsu is at his peak right now, and the curve hasn't flattened.
The record covers 6 seasons (2020/21–2025/26) across 2 clubs — 203 appearances, 16 goals and 23 assists.
His best campaign on record is 2021/22 at Sagan Tosu — Season rating 35, 6 goals and 3 assists in 37 games. 2025/26 was the leap — Season rating up 23 points at Kashiwa Reysol. Form is on a climb — up 15 Season points across his last 3 full seasons.
| Season | Club | Apps | G | A | Rating | Season |
|---|---|---|---|---|---|---|
| 2025/26 | Kashiwa Reysol | 37 | 3 | 10 | 30 | 34 |
| 2024/25 | Kashiwa Reysol | 33 | 0 | 1 | 30 | 11 |
| 2023/24 | Kashiwa Reysol | 30 | 1 | 1 | 33 | 18 |
| 2022/23 | Kashiwa Reysol | 33 | 4 | 5 | 45 | 28 |
| 2021/22 | Sagan Tosu | 37 | 6 | 3 | 52 | 35 |
| 2020/21 | Sagan Tosu | 33 | 2 | 3 | 52 | 31 |
| Competition | Apps | Min | G | A | Rating |
|---|---|---|---|---|---|
| J1 League | 37 | 2684 | 3 | 10 | 7.0 |
| Date | Competition | Opponent | Res | Status | Min | G | A | Rating |
|---|---|---|---|---|---|---|---|---|
| Feb 9 | Friendlies Clubs | A JEF United Chiba | 3-0 | Not in squad | — | |||
| Feb 15 | J1 League | A Avispa Fukuoka | 1-0 | Played | 90 | 7.0 | ||
| Feb 22 | J1 League | H Kawasaki Frontale | 1-1 | Played | 90 | 6.9 | ||
| Feb 26 | J1 League | H Cerezo Osaka | 2-1 | Played | 77 | 1 | 6.9 | |
| Mar 2 | J1 League | A Urawa | 2-0 | Played | 74 | 1 | 7.5 | |
| Mar 8 | J1 League | H Kashima | 1-3 | Played | 58 | 6.6 | ||
| Mar 16 | J1 League | A Sanfrecce Hiroshima | 1-1 | Played | 65 | 7.0 | ||
| Mar 20 | J-League Cup | A Azul Claro Numazu | 1-0 | Not in squad | — | |||
| Mar 29 | J1 League | H Tokyo Verdy | 0-0 | Played | 90 | 6.5 | ||
| Apr 2 | J1 League | A Kyoto Sanga | 1-1 | Played | 68 | 7.0 | ||
| Apr 6 | J1 League | H Gamba Osaka | 1-0 | Played | 90 | 7.9 | ||
| Apr 11 | J1 League | A FC Tokyo | 1-1 | Played | 68 | 6.9 | ||
| Apr 16 | J-League Cup | A Fukushima United | 3-2 | Not in squad | — | |||
| Apr 20 | J1 League | A Shonan Bellmare | 1-0 | Played | 74 | 7.3 | ||
| Apr 26 | J1 League | H Albirex Niigata | 1-1 | Played | 87 | 7.3 | ||
| Apr 29 | J1 League | A Nagoya Grampus | 2-1 | Played | 32 | 6.6 | ||
| May 6 | J1 League | H Shimizu S-pulse | 1-0 | Played | 22 | 6.3 | ||
| May 10 | J1 League | H Fagiano Okayama | 2-0 | Played | 78 | 1 | 7.3 | |
| May 14 | J1 League | A Yokohama F. Marinos | 2-0 | Played | 45 | 6.7 | ||
| May 17 | J1 League | A Machida Zelvia | 0-3 | Unused sub | 0 | — | ||
| May 21 | J-League Cup | A Renofa Yamaguchi | 2-0 | Not in squad | — | |||
| May 25 | J1 League | A Yokohama FC | 1-1 | Played | 68 | 7.3 | ||
| May 31 | J1 League | H Vissel Kobe | 1-3 | Played | 66 | 6.5 | ||
| Jun 4 | J-League Cup | A Tokyo Verdy | 3-0 | Not in squad | — | |||
| Jun 8 | J-League Cup | H Tokyo Verdy | 2-1 | Not in squad | — | |||
| Jun 11 | Emperor Cup | H Toyo University | 0-2 | Not in squad | — | |||
| Jun 15 | J1 League | A Tokyo Verdy | 3-0 | Played | 72 | 1 | 6.9 | |
| Jun 21 | J1 League | H Kyoto Sanga | 3-3 | Played | 89 | 1 | 7.0 | |
| Jun 28 | J1 League | A Shimizu S-pulse | 2-0 | Played | 66 | 1 | 7.0 | |
| Jul 5 | J1 League | H FC Tokyo | 1-0 | Played | 86 | 1 | 7.9 | |
| Jul 20 | J1 League | A Kashima | 2-3 | Played | 85 | 1 | 7.2 | |
| Aug 10 | J1 League | H Shonan Bellmare | 2-0 | Played | 90 | 1 | 7.7 | |
| Aug 17 | J1 League | A Fagiano Okayama | 1-2 | Played | 66 | 6.6 | ||
| Aug 22 | J1 League | H Urawa | 4-2 | Played | 90 | 1 | 7.3 | |
| Aug 31 | J1 League | H Avispa Fukuoka | 2-1 | Played | 80 | 1 | 7.7 | |
| Sep 3 | J-League Cup | A Yokohama F. Marinos | 4-1 | Not in squad | — | |||
| Sep 7 | J-League Cup | H Yokohama F. Marinos | 1-0 | Not in squad | — | |||
| Sep 12 | J1 League | A Vissel Kobe | 0-0 | Played | 70 | 6.6 | ||
| Sep 20 | J1 League | A Cerezo Osaka | 1-1 | Played | 74 | 6.9 | ||
| Sep 23 | J1 League | H Sanfrecce Hiroshima | 0-0 | Played | 23 | 6.9 | ||
| Sep 28 | J1 League | A Kawasaki Frontale | 4-4 | Played | 90 | 1 | 7.2 | |
| Oct 4 | J1 League | H Yokohama F. Marinos | 1-0 | Played | 87 | 7.5 | ||
| Oct 8 | J-League Cup | A Kawasaki Frontale | 1-3 | Not in squad | — | |||
| Oct 12 | J-League Cup | H Kawasaki Frontale | 4-1 | Not in squad | — | |||
| Oct 18 | J1 League | A Gamba Osaka | 5-0 | Played | 90 | 1 | 7.2 | |
| Oct 25 | J1 League | H Yokohama FC | 2-0 | Played | 90 | 7.2 | ||
| Nov 1 | J-League Cup | H Sanfrecce Hiroshima | 1-3 | Not in squad | — | |||
| Nov 8 | J1 League | H Nagoya Grampus | 1-0 | Played | 90 | 7.0 | ||
| Nov 30 | J1 League | A Albirex Niigata | 3-1 | Played | 28 | 6.7 | ||
| Dec 6 | J1 League | H Machida Zelvia | 1-0 | Played | 76 | 6.7 |