2014 Australian Open - Li Na
IN PHOTO: Retired tennis star Li Na REUTERS

Li Na announced her retirement from tennis in a letter that she penned and shared to her Facebook fans on Sept. 18. Li's decision to retire from tennis was reportedly influenced by a number of things.

According to Sports Illustrated's (SI) Courtney Nguyen, Li stepped away from the sport because she wants to settle down and have kids with her husband, Jiang Shan. In addition to starting her own family, Li also wants to put up her own tennis academy, which will be named Li Na Tennis Academy. She's reportedly already looking for the best location for her school, which she says will teach Western coaching approaches. She also aims to be more involved with philanthropy work.

Li admitted that she felt sad saying goodbye to the sport that she played for more than half of her life. "I was sad because tennis was with me for 24 years," Li told SI. She said saying goodbye to tennis was like saying goodbye to her family.

However, Li said she had to listen to her body. It was in 2008 when Li first suffered an injury on her right knee. She had to pull out of tournaments due to the repetitive and worsening knee injury. In the 2014 season, Li last played at the Wimbledon Championships, where she received a third round exit after losing to Zahlavova Strycova. Li did not play in July and forced to withdraw from tournaments in Montreal, Cincinnati, and the US Open because of the knee injury.

Li further revealed that her decision to retire from tennis did not happen overnight. She said she thought about it for a long time. She even turned to her doctors and ask them the best route for her career. In the end, she followed her heart.

"I say I make the decision, I cannot play anymore." Li said.

With Li's retirement decision, she is ready to begin another chapter in her life. She said she would like to have two kids and a couple of dogs in their household.

Li's career-best ranking in the Women's Tennis Association is second place. She has won nine WTA singles title. She has also won two Grand Slam titles at the 2011 French Open and the 2014 Australian Open. She ranked 5th in the WTA rankings when she announced her retirement.