2023 In 2023, Nishi and Sato won three international titles. They secured their first
World Tour title at the
Vietnam Open, defeating
Ruttanapak Oupthong and
Jhenicha Sudjaipraparat in the final. The pair subsequently won the
Kaohsiung Masters by defeating the top-seeded Indonesian pair of
Dejan Ferdinansyah and
Gloria Emanuelle Widjaja. They also won the
Indonesia International and finished as runners-up at the
Indonesia Masters Super 100.
2024 In 2024, Nishi competed in both men's and mixed doubles. He formed a men's doubles partnership with
Kakeru Kumagai. The pair finished as runners-up at the Super 100
Odisha Masters and the
Kazakhstan International. In mixed doubles, Nishi and Sato won the
Saipan International title and advanced to the quarter-finals of the Super 300
Orléans Masters. The pair achieved a career-high world ranking of No. 30 on 30 July. On the national circuit, they finished as runners-up at the All Japan Championships after an injury to Sato forced them to retire in the final.
2025 Nishi turned professional on 1 April, joining the
BIPROGY team following his graduation from university. He was part of the Japanese squad that earned a bronze medal at the
Asia Mixed Team Championships. In mixed doubles, he and Sato made their
Asian Championships debut, eliminated in the first round after winning their initial round-robin matches. The pair later secured their first national title at the
Japan Ranking Circuit, defeating Olympic medalist
Yuta Watanabe and
Misaki Matsutomo in the final. Their partnership concluded on 1 July, following Sato's retirement from professional badminton. Focusing on men's doubles with Kumagai, Nishi won his first international title as a pair at the
Northern Marianas Open. He was part of the Japanese team that won Japan's first men's team title at the
Asia Team Championships. In the final against China, Nishi and Kumagai defeated
He Jiting and
Ren Xiangyu in three games. Nishi achieved a career-high world ranking of 24 on 14 April. == Achievements ==