Stanislas Wawrinka's wife, Illham Vuilloud, tells Swiss media that the couple separated in September.
"He left us after he returned from the Davis Cup on September 20," Vuilloud was quoted as saying. "He said, 'Since I got my new coach [Peter Lundgren], I've changed—I have other needs, other desires. Tennis has once again become my priority. I've got another five years, I'll give it everything.'"
She added, "There could have been a different solution, if he had spoken to me about it."
The couple were married just over a year ago, with daughter Alexia born last February.
"Our main concern now is to look after the best interests and education of our daughter Alexia," Wawrinka said as part of a statement posted online.