Amelie Mauresmo has revealed the reasons for her coaching split with Andy Murray, explaining they "reached the end" of what they could achieve and he was a "complex" player to work with.

Murray became the first high-profile tennis player to hire a woman as a coach when he took on Mauresmo in June 2014, but they ended their working relationship on May 9.

Under the guidance of Mauresmo, a two-time Grand Slam champion and former world No. 1, Murray won his first clay-court titles last year in Munich and Madrid.

However, he failed to add to his two Grand Slam titles. He's ranked No. 2.

"I had the impression that we'd reached the end of what we could do professionally together," Mauresmo said on Saturday in an interview with L'Equipe magazine. "Andy is complex. On a court, he can be the opposite to how he is in life. It can be disconcerting. I was there to help him. I had the feeling that I couldn't improve things anymore."

The Frenchwoman gave birth to her first child in August and took six months off from coaching.

"I reduced the number of weeks that I could be present since the Australian Open and ... effectively, we've spent little time together," said Mauresmo, who won Wimbledon and the Australian Open. "It turned out to be a difficult period for him, where I couldn't help him."

Mauresmo did not elaborate further over the reasons for their parting of ways, except to say that it was inevitable.

"I don't want to go into detail too much. Everyone could see certain things," Mauresmo said, in reference to her absence in Murray's box during the Miami Masters. "I no longer wanted to be there. I wanted to try something else."

However, she praised Murray's intense work ethic and hailed him as a champion.

"I liked the way Andy worked; I liked working with his team. Andy is someone with a great capacity to listen and to analyze," Mauresmo said. "He's very curious and always trying to learn. That's what makes great champions."