Tseng Chun-hsin

Tseng Chun-hsin (born 8 August 2001), also known as Jason Tseng, is a Taiwanese tennis player. He has a career high ATP singles ranking of World No. 83, achieved on 8 August 2022. Tseng is currently the No. 1 Taiwanese player on the ATP tour.

He was also the ITF junior No. 1, first reaching this ranking on 11 June 2018 after winning the French Open Boys' Singles. He is also part of the Chinese Taipei Davis Cup team since 2018, with a W/L record of 1–0.

Early and personal life
Tseng began playing tennis at the age of five with his father, who worked at a night market in Taiwan. He first trained in elementary school team located in Yonghe District, New Taipei City.

He is nicknamed "the Night Market Champion" by the Taiwanese media as his parents used to sell Tanghulu at the Lehua Night Market in New Taipei City in order to support his tennis career.

Pre-2019: Junior years
He continued his training at the Mouratoglou Tennis Academy in France from age 13 to 17. During that period, he won singles title at the Petits As in 2015.

In 2018, He won his first ITF Futures event in Vietnam. He won the boys' singles title at the French Open and claimed the Wimbledon boys' singles title in the following month.

2019: ATP and Masters debut
He made his ATP debut at the 2019 Miami Open as a wildcard.

In the 2019 Summer Universiade, Tseng won the gold medal in men's singles.

2021–2022: Challenger breakthrough, Major & top 100 debut
In December 2021, Tseng won his first ATP Challenger title in Maia, Portugal. He made his debut in the top 200 at World No. 188 on 20 December 2021.

He made his Grand Slam debut at the 2022 Australian Open where he received a wildcard.

The following month in February 2022, Tseng won his second ATP Challenger title in Bangalore, India. In April 2022, Tseng won his third ATP Challenger title in Murcia, Spain. He reached a career-high ranking of World No. 110 on 16 May 2022.

He qualified for his second Grand Slam at the 2022 French Open to make his debut at this Major. He lost in the first round in five sets in a match that lasted 4 hours 23 minutes against João Sousa.

As a result of reaching the semifinals in Bratislava, Tseng made his debut in the top 100 at No. 97 on 13 June 2022.

He participated in the 2022 Next Generation ATP Finals as the sixth seed.

2023–2024: First Masters win, back to top 200
Ranked No. 380, he made his debut in qualifying at the Masters 1000, the 2023 Rolex Shanghai Masters. He qualified for the main draw and defeated Alexander Shevchenko on his debut at this tournament, recording his first Masters win. As a result, he moved close to 80 positions back up, one position shy of the top 300 on 16 October 2023.

In March 2024, he won his fourth Challenger at the 2024 Kiskút Open in Szekesfehevar, Hungary and returned to the top 250 on 18 March 2024. Following his fifth Challenger title at the 2024 Internazionali di Tennis Città di Vicenza and a final showing at the 2024 UniCredit Czech Open in Prostejov, he moved again 80 positions back up and returned to the top 175, on 10 June 2024.