Shenzhen, China:Former French Open champion Michael Chang has quit as coach of Chinese tennis player Peng Shuai.
Peng is China's top-ranked female doubles player and is the top 50 singles rankings along with another Chinese, Li Na.
She has singles victories this year over two former top-ranked players: Martina Hingis and Amelie Mauresmo.
Speaking on Friday about plans to set up a tennis academy at the Mission Hills Golf Club in southern China, Chang said he had stepped down because coaching Peng was requiring too much time.
"They wanted me to travel with her (Peng) to all the events and I just don't have the time to do that," he said. "Obviously we would always keep our door open if she ever needs anything."
A Chinese-American, Chang has been rebuffed in recent months by officials of the China Tennis Association as he has attempted to get involved nurturing China's young talent and coaching Olympic hopefuls.
"I think if I was more heavily involved with preparing the Olympic team, the opportunity for them to do well and to possibly win another medal or multiple medals in my opinion would increase," he said.
Chang took a shot at Chinese officials saying they needed an "open mind" in looking at the ways in which they train young tennis players. He suggested training methods, strategy and tennis technology all needed to be examined.
"In my opinion there are some things that need to be revised," he said. "I don't think there are major things but there are some things that can be implemented to help them go to the next level.
"China's been an incredible place for racket sports - ping pong, badminton - the best in the world. Tennis shouldn't be an exception to that."
Chang and Tenniel Chu, the executive director of Mission Hills, said Chang's new tennis academy would open next year on the grounds of the sprawling golf resort.
Mission Hills is the world's largest golf complex with 12 courses spread over 15 square kilometers (5.8 square miles).
Named the Mission Hills-Michael Chang Tennis Academy, the facility will have at least 50 outdoor courts, with clay-courts and indoor courts under construction.
Chang did not say how much players would pay to train at the facility, but said scholarships might be available to promising talent.