Juncheng Shang

In 2019, Shang was the first player born in 2005 to win a tournament on the ITF Junior Circuit.

Shang played in the French Open and reached the quarterfinals, in which he lost to Sean Cuenin in two sets. He also played in the Wimbledon Junior Event and reached the semifinals. He lost to Victor Lilov in two sets. In the US Open Junior Event, he reached the final and lost to Daniel Rincón in two sets (2–6, 6–7⁶).

Shang made his debut on the professional tour, after receiving a wildcard to play in the main draw of the ATP Tour 500 event at the 2022 Rio Open, after Juan Martín del Potro announced his retirement from professional tennis. Shang was defeated by Pedro Martínez in the first round. He received a wildcard into the qualifying draw of Indian Wells, where he beat Francisco Cerúndolo in the first round and his opponent Mats Moraing retired in the second. Having qualified into the main draw, he became the first Chinese man to play at Indian Wells and the first player from his country to qualify for an ATP Masters 1000. He was defeated by Jaume Munar in straight sets. He also received a wildcard for the main draw at the 2022 Miami Open.

He won his first title in Lexington, United States becoming the youngest Chinese player to win a trophy in the Challenger Tour history and the youngest since Carlos Alcaraz in 2020 Alicante. He reached the top 200 at world No. 195 on 19 September 2022.

Shang made his Grand Slam debut by qualifying at the Australian Open, after defeating Fábián Marozsán, 16th seed Fernando Verdasco and Zsombor Piros, becoming the youngest male player at the tournament and the youngest Grand Slam men's qualifier since 17-year-old Carlos Alcaraz at the 2021 Australian Open. He became the 10th Chinese mainland player to reach the main draw at this Major in 2023. It was the first time a male Chinese trio was set to compete in a major singles draw in the Open era (since 1968) and the first in all of Australian Open history (since 1905). Shang defeated Oscar Otte in the first round, becoming the first Chinese male player to win a match at the Australian Open in the Open Era. He then lost in straight sets to Frances Tiafoe in the second round. He received a wildcard for the main draw at the 2023 Miami Open. At the French Open, he qualified for his second Grand Slam in a row by defeating Pablo Cuevas, Marozsán and Renzo Olivo.

He reached the top 150 on 17 July 2023. The following week, he competed at the 2023 Atlanta Open where he lost to Kei Nishikori in the second round and his second ATP 500 in Washington D.C. defeating Emilio Gómez and 14th seed Ben Shelton before losing to second seed Frances Tiafoe.

He played his first ATP tour event in his homeland at the 2023 Zhuhai Championships where he lost to Mackenzie McDonald. He received a wildcard for the next Asian tournaments the China Open in Beijing, where he lost to Japanese Yoshihito Nishioka, and the 2023 Rolex Shanghai Masters, where he lost to Japanese Yosuke Watanuki, both in the first round.

Having received a wildcard for the 2024 ATP Hong Kong Tennis Open tournament, he reached his maiden ATP quarterfinal with wins over seventh seed Laslo Djere, and then Botic van de Zandschulp in a 3 and 1/2 hours, close match with three tiebreaks 6–7(5) 7–6(2) 7–6(2). Next he defeated third seed Frances Tiafoe in straight sets to reach his first career ATP semifinal, before losing to eventual champion Andrey Rublev in a three-set match.

He received a wildcard for the Australian Open where he defeated Mackenzie McDonald in the first round and qualifier Sumit Nagal in the second to reach the third round of a Major for the first time in his career. He retired in the third set in his next match against world No. 2 Carlos Alcaraz. In March, he qualified for the 2024 BNP Paribas Open defeating Yoshihito Nishioka and Facundo Bagnis and recorded his first Masters main draw win over Jordan Thompson after a fifth match point. He was awarded a wildcard into the main draw at the 2024 Miami Open and in April, he also received a wildcard for the 2024 Madrid Open where he defeated qualifier Corentin Moutet in a four hour epic match. At the 2024 Italian Open he replaced 13th seed Ugo Humbert as a lucky loser directly in the second round. He reached the top 100 at world No. 89 on 20 May 2024.

At the 2024 Atlanta Open he reached his second ATP semifinal of his career as a qualifier, defeating two Americans, wildcard Andres Martin and top seed Ben Shelton, and then eight seed Max Purcell. As a result he reached the top 75 in the rankings on 29 July 2024. He reached another Grand Slam third round at the US Open with wins over 27th seed Alexander Bublik and Roberto Carballés Baena and entered the top 70 in the rankings on 9 September 2024. At the 2024 Chengdu Open he defeated wildcard Kei Nishikori in the first round. Next he upset eight seed Roman Safiullin, second seed Alexander Bublik and Yannick Hanfmann to reach his first ATP Tour final and moved to the top 55 in the rankings on 23 September 2024. He defeated Lorenzo Musetti in the final to claim his maiden ATP Tour title and became only the second Chinese titlist in the Open Era after Wu Yibing. On 14 October 2024, after a second-round showing in Shanghai, Shang reached world No. 49, becoming the first man born in 2005 or later to reach the Top 50 in ATP rankings history.