PARIS, May 29 (Xinhua) -- Shang Juncheng was only one set away from becoming the first Chinese mainland male player to win a match in the French Open main draw, before slipping to a bitter five-set defeat to Juan Pablo Varillas of Peru on Monday.

The 18-year-old, coming through qualifying in Paris, lost his first clay court match 4-6, 2-6, 6-2, 6-3, 6-1 in three hours and 22 minutes.

No men's singles player from the Chinese mainland had appeared on the red clay in Paris since the Open era, but when Shang's match kicked off on Court 5 in Roland Garros, history was already made.

Shang even once seemed to be able to go further, when he showed dominance in the second set, breaking twice in the fourth and eighth game to take a two-set lead.

But Varillas, ranking 94th, managed a strong fight back while Shang was stuck in a left wrist injury which forced him to call for a medical timeout in the fifth set.

"After the second set, my physical condition slightly declined because I haven't been training much lately," said Shang, who revealed that he has been infected with mononucleosis recently.

"I would start feeling exhausted after playing only 10 minutes, and it's been affecting me a lot recently, and even I can't sleep well. So I would already be very happy to come here," Shang added.

The world No. 200 failed to earn a single break in the remaining three sets, only to see his opponent turn the tide to secure his first Grand Slam win.

Varillas will next face Spanish veteran Roberto Bautista Agut after the 19th seed dispatched another Chinese player Wu Yibing 7-6(4), 6-1, 6-1.