LONDON - The women's singles eighth seed Zheng Qinwen from China was upset by qualifier Lulu Sun of New Zealand in the opening round at the Wimbledon Championships on Monday.

Zheng, 21, took the first set 6-4 without too much trouble but was broken soon when the second set began. The world No. 8 made eight double faults in all before losing the following two sets 6-2, 6-4, suffering a first-round exit in the All England Club as she did last year.

While Zheng's compatriot, the No. 32 seed Zhang Zhizhen, grabbed his first Wimbledon main draw win by beating French qualifier Maxime Janvier 7-6(4), 6-3, 6-2 and his 19-year-old countryman Shang Juncheng achieved the same breakthrough after knocking out Cristian Garin from Chile 7-5, 6-4, 6-4.

"My eyes started swelling since yesterday, and the situation got more serious today. I have to say it did bother me a little," said Australia Open finalist Zheng.

Zheng also revealed that her right upper arm had not been right for three days. "I have to be very careful during training as I feel painful when I serve. I was worried if it's ok before today's match. Even though it's all right in the first set, I started to feel the pain in the second set. My game was not as aggressive as it used to be, and my serves were not strong enough."

However, Zheng believed that if her play had been more clinical in some key points, she would probably still be able to win the match.

World No. 2 Coco Gauff didn't give her opponent Caroline Dolehide any chance to become a dark horse as the American swept her compatriot 6-1, 6-2 in 65 minutes.

Last year, Gauff was shocked in the first round at Wimbledon by compatriot Sofia Kenin, who will face world No.1 Iga Swiatek on Tuesday.

Just a few hours before her opening match, world No.3 Aryna Sabalenka decided to withdraw from this year's Wimbledon Championships due to a shoulder injury.

The Belarusian ace was replaced by lucky loser Erika Andreeva from Russia, who then defeated American Emina Bektas 7-6(5), 3-6, and 6-3 to reach the second round.

In the men's singles event, world No. 1 Jannik Sinner defeated German Yannick Hanfmann 6-3, 6-4, 3-6, 6-3 to set up an Italian derby in the second round against Matteo Berrettini after the 2021 finalist beat Hungarian Marton Fucsovics in four sets.

Defending champion Carlos Alcaraz of Spain saw off qualifier Mark Lajal from Estonia 7-6(3), 7-5, 6-2.

"Every time that I can, I try to go to play golf. It helps me a lot to turn off my mind a little bit, not to think about the match," said Alcaraz, who was seen playing golf Sunday night. "This is a sport that I love to play, and it can help me a lot to stay calm, not to think about tennis."