In Hamada's senior year with Miyazaki Technical High School, he reached the spring koshien.

As the team's ace, he pitched a full game for only two hits in the first round against Maebashi Technical High School but came up short in the second round against Kohei Arihara's Koryo High school conceding a run in the final inning in a walk-off loss.

On the 10 April 2015, Hamada was registered for the first team[2] and on 19 April made his first team debut against the Hiroshima Carp in the 8th inning where he gave up a career first home run to Takayoshi Noma followed by a succession of 5 hits resulting in 3 earned runs and leaving him in tears.

[4] While there was much expectation over the development of Hamada, this would remain his only game of the season as he was relegated to the farm team for the remainder of the year.

[5] In the 2015 off-season he along with teammates Iori Katsura, Shuhei Takahashi, Shota Tomonaga and Junki Kishimoto were loaned to the Taiwanese winter league[6] Hamada failed to make any appearances for the first team in the 2016 season with his contract being downgraded to a trainee contract for 2017.