In his MMA debut, Arai faced Ryosuke Ogawa at Professional Shooto 3/21 on March 21, 2016.
[2] Arai faced Takamasa Kiuchi at Professional Shooto 2022 Vol.
[3] Arai faced Ryohei Kurosawa at Professional Shooto 2022 Vol.
[7] Arai faced Yo Otake at Professional Shooto 2022 Vol.
[14] Arai faced Nkazimulo Zulu on September 29, 2024 at RIZIN 48, and lost the bout via technical knockout in the first round.