Kanta Tsuneyama

In 2016, Tsuneyama won his first senior international title at the Finnish Open in April, defeating Nguyễn Tiến Minh of Vietnam in the final. He also reached the finals of the Austrian Open in February and the Spanish International in June, where he was runner-up to Anders Antonsen of Denmark on both occasions. Additionally, Tsuneyama advanced to his first BWF Grand Prix Gold final at the U.S. Open in July, where he lost to Lee Hyun-il of South Korea. Starting the season with a world ranking of No. 140, Tsuneyama entered the top 50 and reached a career-high of world No. 45 by 28 August 2016.

In 2017, Tsuneyama won two international titles, beginning with the Austrian Open in February. He followed this by winning his first Grand Prix Gold title at the Canada Open in July, defeating his compatriot, Kento Momota, in the final. Momota was competing in his first international tournament following a suspension. By the end of the year, Tsuneyama had broken into the top 30, reaching a new career-high ranking of world No. 27.

In 2018, Tsuneyama won his first BWF World Tour title at the Thailand Open, defeating Tommy Sugiarto in the final. He was the first Japanese men's singles player to win the title in the tournament's 34-year history. At the World Championships in Nanjing, Tsuneyama reached the quarterfinals for the first time. He defeated the 12th seed, Anthony Sinisuka Ginting, before being eliminated by Liew Daren of Malaysia.

In team competitions, Tsuneyama contributed to the Japanese team's silver medal at the Thomas Cup in Bangkok. During the semifinal against defending champion Denmark, with the tie at 2–2, he won the decisive fifth match against Jan Ø. Jørgensen to secure a 3–2 victory and advance the team to the final. Later that year, he was part of the team that won a bronze medal at the Asian Games in Jakarta.

Tsuneyama won his second World Tour title at the Korea Masters. Entering the tournament unseeded, his path to the final included a victory over sixth seed Srikanth Kidambi, before he defeated two-time Olympic champion Lin Dan 24–22, 21–12 in the final. Earlier that year at the Japan Open, he upset reigning Olympic champion Chen Long 21–14, 21–17 in the first round. He reached a career-high world ranking of No. 10 as of 26 November 2019.

In team competition, Tsuneyama was part of the Japanese squad that finished as runner-up at the Asian Mixed Team Championships. Individually, he reached the third round at the World Championships in Basel, where he was defeated by Denmark's Anders Antonsen, the eventual runner-up. Tsuneyama concluded the year by reaching the semifinals of the All Japan Badminton Championships, where he lost to Kenta Nishimoto, securing a bronze medal for the third consecutive year.

In early 2020, Tsuneyama was a member of the Japanese team that won the bronze medal at the 2020 Badminton Asia Team Championships in Manila. Later that year, he finished as the runner-up at the All Japan Badminton Championships, losing to Kento Momota in the final.

Tsuneyama made his Olympic debut at the 2020 Summer Olympics in Tokyo, held in 2021. In the men's singles event, he advanced from his group stage by defeating Julien Paul of Mauritius and Ygor Coelho of Brazil. He was subsequently eliminated in the round of 16 by Indonesia's Anthony Sinisuka Ginting.

In team competitions later in 2021, Tsuneyama contributed to Japan winning a silver medal at the 2021 Sudirman Cup in Vantaa and a bronze medal at the 2020 Thomas Cup in Aarhus. In October, Tsuneyama won his first Super 750 title at the 2021 French Open, defeating Chou Tien-chen of Chinese Taipei in the final. He advanced to the final after his compatriot, Kento Momota, retired from their semifinal match due to injury.

In 2022, Tsuneyama began the season by reaching the quarterfinals of the Asian Championships, where he lost to Lee Zii Jia. In May, he earned a bronze medal with the Japanese men's team at the Thomas Cup in Bangkok. Later that year, he advanced to the quarterfinals at the Malaysia Masters in July, defeating compatriot Kento Momota before falling to Prannoy H. S. He also reached the quarterfinals at the Japan Open, where he beat Srikanth Kidambi before losing to Anders Antonsen. However, his participation in the World Championships ended in the opening round.

Tsuneyama began the 2023 season in January by reaching the semifinals of the Super 1000 Malaysia Open. His run included a quarterfinal victory over Anthony Sinisuka Ginting before he was defeated by world No. 1 Viktor Axelsen. In March, he finished as the runner-up at the Spain Masters, losing to compatriot Kenta Nishimoto in the final. The following month, he secured a bronze medal at the Asian Championships after losing his semifinal match to the eventual champion, Anthony Sinisuka Ginting. At the World Championships in August, his campaign concluded in the third round with a defeat by Nishimoto. Later in the season, Tsuneyama reached the semifinals of the Arctic Open in October. In November, he also advanced to the semifinals of the China Masters, where he was defeated by the eventual champion, Kodai Naraoka. In team competitions, he contributed to Japan's bronze medal wins at both the Sudirman Cup and the Asian Games.

In 2024, Tsuneyama concluded his professional career. He participated in nine tournaments, with his best result being a second-round finish at the Japan Open in August. Following this tournament, on 22 August 2024, he announced his retirement from international badminton and withdrew from the Japanese national team.