Never a power hitter and never will he be, China's rising ace Shang Juncheng leans on his quick legs and tactical variety to outwit size and strength, enabling him to survive the brutally competitive world of men's tennis.

A sudden bone fracture in his right foot sustained at the Australian Open, however, cast a shadow on his meteoric rise on the ATP Tour, posing a serious threat to a budding career that has been built upon his speed and agility.

The 20-year-old did pay a heavy price — he underwent the first surgery of his life, spent almost half a year in rehab and took a nosedive in the rankings, plummeting to No 238 all the way from a career-high No 47 a year ago.

Yet, he left fans convinced that none of the setbacks would wear him down, proving it at the last and highest-caliber tournament of the year on home soil, the Rolex Shanghai Masters.

Relying on his familiar winning formula of fast movement combined with pinpoint shots and long rallies, Shang stunned world No 10 Karen Khachanov in straight sets in a second-round encounter with the big-serving Russian on Saturday to notch his first win over a top-10 opponent since he turned pro in 2021.

The biggest win of his career to date also helped him reach the third round at a top-tier ATP 1000 tournament for the first time in his career, making him the youngest among three Chinese men who have advanced that far at a Masters tournament.

Only his older compatriots Zhang Zhizhen and Wu Yibing have accomplished the feat, also in Shanghai in 2023 and 2024, respectively.

The victory was Shang's fifth career win on the ATP 1000 series, where, aged 19, he became the youngest Chinese man ever to register a main-draw triumph at that level with a straight-sets win over Jordan Thompson at Indian Wells, California, in March last year.

The serial setter of "youngest-ever" records in Chinese men's tennis will next take on Portugal's world No 51 Nuno Borges on Monday in the round of 32, looking to write more history under his name.

"It was an unbelievable match against Karen today. He's a very solid top-10 player. Coming into the match I didn't think too much, I just wanted to put on a show for the people," Shang said during his post-match on-court interview.

"I didn't start perfectly, but I kept fighting, kept focusing, no matter if I was winning or losing, though I'm glad that I got the win. Overall, I am happy with my performance, and would have been even if I had lost."

Apart from his composure and precision, Shang attributed his scintillating form to the energy from his family who were cheering in the stands, including vocal support and some technical tips from his grandmother.

"I am super happy to have family here," Shang said before rushing into the stands to hug his most senior cheerleader. "Winning here, on such a big stage, means a lot, especially at home. Having them watch me do it is incredible."

Shang's deeper run in Shanghai, after being eliminated in the second round last year by world No 1 Carlos Alcaraz, has served him up a much-needed confidence boost following his return from the long injury layoff.

Since coming back to play in July during the North American hard-court swing, Shang has suffered five losses, including two straight defeats recently at home in the ATP 250 Chengdu Open and ATP 500 China Open, as he tried to pick up his pace and regain his form.

It seems that his form has arrived at the right time.

The Shanghai Masters, as the highest-ranked event on the China Swing, offers the most generous prize pool and ranking-point haul during the final stretch of the season, and by fighting into the round of 32 Shang has already collected 50 points, helping him climb back to No 215 in the live ATP rankings, as well as pocketing a bonus of at least $60,400.

To get over the hump mentally, following an injury that hampered his strength in movement, is worth far more, though, according to Shang.

"I am always a fast-moving player, and I've been used to counting on my advantage in speed when facing bigger and more powerful opponents," said Shang, who won his career first ATP Tour title in Chengdu last year thanks to his rapid-fire game.

"I feel like I've overcome a hurdle in my mind with the win over a top-10 opponent, and by getting over that mental obstacle, I've found the confidence in myself again.

"Of course, I won't be able to prevail every time I face a player in the top 10. But, with faith restored in myself physically and mentally, I feel like I could do it every time I step on the court on my best day."

Shang and Khachanov twice traded breaks in the opening set. In the second set, Shang rode a string of winners to victory, claiming the final three games from 3-3 and rattling off the final six points of the match.

"Against players like Karen, you might only have one chance to close it out," said Shang. "If I don't, it might be the match, it might be a grind in the third set, you never know. But, I'm glad that I kept the focus, and that, in the end, it went smoothly."

In an earlier second-round match on Saturday, China's current top-ranked man, Buyunchaokete, who is ranked 121st, was beaten by Italy's No 26 seed Luciano Darderi 6-4, 6-4 at the Grandstand 2 Court, ending his Shanghai campaign earlier than expected, leaving Shang as the last local favorite standing.

sunxiaochen@chinadaily.com.cn