Ewing, one of the NBA's 50 greatest players, had been on coach Jeff Van Gundy's staff for three seasons.

He is credited with the development of Rockets centre Yao Ming, who had the best season of his career in 2005-06.

"It was a difficult decision to resign because I enjoy coaching," said Ewing.

"I love working with Jeff and the rest of the staff, and our players are really good guys. But my children are getting older and I want to spend more time with them.

"I'm sure at some time I will get back into coaching, but right now I need to focus completely on my kids."

One of Ewing's children, Patrick jnr, is a junior who transferred last year from Indiana to Georgetown University, the elder Ewing's alma mater.

Ewing played 17 years in the NBA, including 15 with the New York Knicks, with which Van Gundy was his coach from 1996-2000.

Following his playing career, Ewing spent one season as an assistant with the Washington Wizards.

"Shortly after the season, Patrick spoke to me about his desire to resign due to family considerations," said Van Gundy.

"I asked him to take a few months to think about his decision. After a great deal of thought, he was convinced that this was the right decision for him and his children."