1. Career
Miyahara's career trajectory shows a steady progression from a promising youth talent to a seasoned professional, marked by his development through top Japanese academies and his contributions to multiple J.League clubs.
1.1. Early life and youth
Kazuya Miyahara was born on March 22, 1996, in Asaminami-ku, Hiroshima, Hiroshima Prefecture, Japan. He is the youngest of three brothers, all of whom progressed through the Sanfrecce Hiroshima youth system. During his elementary school years at Hiroshima Municipal Midori Elementary School, Miyahara played for Satō FC, primarily as a forward or an attacking midfielder.
In 2008, he joined Sanfrecce Hiroshima Jr. Youth, where he continued to play as an attacking midfielder. During his time at Hiroshima Municipal Jōnan Junior High School, he contributed to the team's third-place finish in the 2010 Japan Club Youth Football Championship (U-15). By his third year of junior high, he transitioned to playing as a defensive midfielder.
Miyahara was promoted to Sanfrecce Hiroshima Youth in 2011, alongside teammates Hayao Kawabe and Naoki Otani. Initially, he remained in an attacking midfield role. He helped the team achieve third place in the boys' division at the 66th National Sports Festival in Yamaguchi, playing as a defensive midfielder. He was also a bench member when the team won the Prince Takamado JFA U-18 Football Premier League in 2011. In his second year of high school (2012), due to injuries among defenders, Miyahara was converted to a center-back and secured a regular starting position, contributing to the team's second consecutive Prince Takamado Premier League title. In 2012, he was selected for the Japan U-16 national team and served as captain during the 2012 AFC U-16 Championship.
In 2013, while still with the youth team and attending Hiroshima Prefectural Yoshida High School, Miyahara, along with Kawabe and Otani, was registered as a Type 2 player for the senior team. On March 25, he and Kawabe signed professional contracts with Sanfrecce Hiroshima, a first for a youth team player still affiliated with the academy. Although he did not make any senior team appearances that year, he played three matches for the Japan U-17 national team at the 2013 FIFA U-17 World Cup. He also helped Sanfrecce Hiroshima Youth achieve runner-up finishes in both the Japan Club Youth Football Championship (U-18) and the J.League Youth Championship.
1.2. Professional club career
Kazuya Miyahara has played for several professional clubs in Japan, establishing himself as a reliable player in various positions.
1.2.1. Sanfrecce Hiroshima
Miyahara officially joined the Sanfrecce Hiroshima senior team in 2014. Initially considered for a defensive midfield role, he quickly found opportunities filling in for injured players as part of a three-man defense. He made his official debut on February 25, 2014, in an AFC Champions League group stage match against Beijing Guoan at Edion Stadium Hiroshima. His J.League debut followed on March 1, 2014, in a J1 League match against Cerezo Osaka at Yanmar Stadium Nagai. He also made five appearances for the J.League U-22 Selection team in the J3 League during the 2014 season.
In 2015, Miyahara scored his first J.League goal on July 11 against Vegalta Sendai at Yurtec Stadium Sendai. He continued to gain experience, making two appearances for the J.League U-22 Selection team in 2015. In the 2016 season, he saw increased playing time as a defensive midfielder during the first stage but was later relegated to the bench.
1.2.2. Nagoya Grampus
On December 26, 2016, Miyahara joined Nagoya Grampus on a season-long loan. He quickly became a regular starter, playing as part of a three-man defense from the opening match of the season. His loan was extended for an additional year on December 30, 2017. He continued to be a key player for Nagoya Grampus throughout 2018.
On December 18, 2018, Nagoya Grampus announced Miyahara's permanent transfer from Sanfrecce Hiroshima. In 2019, he was a central figure for the team, making 31 league appearances and scoring four goals. However, the 2020 season was challenging for Miyahara, as he was affected by the COVID-19 pandemic and injuries, limiting him to just five league appearances. He remained with Nagoya Grampus until the end of the 2022 season, when his contract expired and he departed the club. During his time at Nagoya, he won the 2021 J.League Cup.
1.2.3. Tokyo Verdy
On December 19, 2022, it was announced that Miyahara would join Tokyo Verdy for the 2023 J2 League season. He has since been a consistent presence for the team in the J2 League.
1.3. International career
Kazuya Miyahara has represented Japan at various youth international levels. He was a member of the Japan U-15 national team in 2011 and the Japan U-16 national team in 2012, where he captained the squad during the 2012 AFC U-16 Championship. In 2013, he played three matches for the Japan U-17 national team at the 2013 FIFA U-17 World Cup. His international youth career continued with selections to the Japan U-19 national team in 2014 and the Japan U-22 national team in 2015.
1.4. Playing style
Miyahara is a versatile player primarily known for his roles as a defensive midfielder or defender. Throughout his youth career, he demonstrated adaptability, starting as a forward or attacking midfielder, then transitioning to a defensive midfielder in junior high, and even playing as a center-back in high school due to team needs. He is right-footed and is recognized for his ability to cover multiple positions effectively, earning him a reputation as an "all-rounder" in the Japanese football scene. He stands at 68 in (172 cm) tall and weighs 148 lb (67 kg).
1.5. Statistics
As of December 21, 2024, Kazuya Miyahara's career statistics are as follows:
| Club | Season | League | National Cup | League Cup | Continental | Play-off Appearances | Total | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Division | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | Apps | Goals | ||
| Japan | League | Emperor's Cup | J.League Cup | AFC | Play-offs | Total | ||||||||
| Sanfrecce Hiroshima | 2014 | J1 League | 4 | 0 | 2 | 0 | 2 | 0 | 1 | 0 | - | 9 | 0 | |
| 2015 | 3 | 1 | 4 | 0 | 5 | 0 | - | - | 12 | 1 | ||||
| 2016 | 13 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | - | 14 | 0 | |||
| Total | 20 | 1 | 6 | 0 | 7 | 0 | 2 | 0 | - | - | 35 | 1 | ||
| J. League U-22 (loan) | 2014 | J3 League | 5 | 0 | - | - | - | - | 5 | 0 | ||||
| 2015 | 2 | 0 | - | - | - | - | 2 | 0 | ||||||
| Total | 7 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7 | 0 | ||
| Nagoya Grampus (loan) | 2017 | J2 League | 41 | 0 | 2 | 0 | - | - | 2 | 0 | 45 | 0 | ||
| 2018 | J1 League | 26 | 0 | 1 | 0 | 2 | 0 | - | - | 29 | 0 | |||
| Total | 67 | 0 | 3 | 0 | 2 | 0 | 0 | 0 | 2 | 0 | 74 | 0 | ||
| Nagoya Grampus | 2019 | J1 League | 31 | 4 | 1 | 0 | 5 | 0 | - | - | 37 | 4 | ||
| 2020 | 5 | 0 | 0 | 0 | 0 | 0 | - | - | 5 | 0 | ||||
| 2021 | 26 | 0 | 3 | 0 | 2 | 0 | 7 | 0 | - | 38 | 0 | |||
| 2022 | 21 | 0 | 1 | 0 | 6 | 0 | - | - | 28 | 0 | ||||
| Total | 83 | 4 | 5 | 0 | 13 | 0 | 7 | 0 | 0 | 0 | 108 | 4 | ||
| Tokyo Verdy | 2023 | J2 League | 41 | 0 | 0 | 0 | - | - | 2 | 0 | 43 | 0 | ||
| 2024 | J1 League | 30 | 0 | 0 | 0 | 1 | 0 | - | - | 31 | 0 | |||
| Career total | 248 | 5 | 14 | 0 | 23 | 0 | 9 | 0 | 4 | 0 | 298 | 5 | ||
1.6. Honours
Kazuya Miyahara has received several team and individual accolades throughout his career:
; Sanfrecce Hiroshima Youth
- Prince Takamado JFA U-18 Football Premier League WEST: 2011, 2012
- Prince Takamado JFA U-18 Football Premier League Championship: 2011, 2012
; Sanfrecce Hiroshima
- J1 League: 2013, 2015
- J1 2nd Stage: 2015
- Japanese Super Cup: 2014, 2016
; Nagoya Grampus
- J.League Cup: 2021
; Individual
- TAG Heuer YOUNG GUNS AWARD Best Eleven: 2018
- J2 League Best XI: 2023