"She's an icon in China ... a huge superstar," said Mike Silverman, director of sport for the New York City Parks Foundation.

"There's no question that tennis in China has never been the same since more than 100 million people watched her win the French Open. It changed everything."

Li conducted a clinic with dozens of children from Silverman's organization on Thursday and her influence was obvious. The foundation uses tennis to promote physical fitness and build self-confidence by offering free instruction to thousands of kids in more than 36 parks throughout New York's five boroughs.

Justin Chong,13, was thrilled to have the opportunity to trade some shots with Li.

"I started playing tennis at the age of seven and joined the program five years ago. I am so glad to have the chance to play with Li Na. Her career shows that if you work hard, you can achieve anything," Chong told Xinhua.

Li added a second major title at the 2014 Australian Open after twice losing in its final, rose to No 2 in the WTA rankings and earned more than 500 singles wins before hanging up her racket.

"At least I always tried my best in tennis on the court," Li said. "If you try everything I think one day for sure there will be payback."