Amelie Mauresmo ended her coaching relationship with Andy Murray because she felt she could not improve the world number two any further, the former world number one said on Saturday.
The Frenchwoman and Murray announced the end of an almost two-year partnership this month, but Mauresmo said the decision had been made some time ago.
"Andy is complex. On court, he can be opposite of what he is in life. It can be confusing. I was here to help. I had the feeling I could not take things further anymore," Mauresmo told L'Equipe Magazine.
"I had the feeling that we were at the end of what we could do professionally. We came to the conclusion that it would be complicated to continue."
With Mauresmo, Briton Murray won seven ATP titles, claiming his first two trophies on clay in Madrid and Munich.
"It was a beautiful adventure. A woman coaching a man, it breaks a few barriers in the world of men's tennis," she said.
"I liked the way Andy works, I liked to work with his team. He's very curious, always in research. That's what makes great champions."
The 29-year-old Murray, a former US Open and Wimbledon champion, is seeded second at the French Open which starts on Sunday.
