Elena Baltacha was "one in a million" and "an absolute gem", according to Judy Murray.
The tennis coach first knew the player known as Bally as a junior in Scotland.
Baltacha, who 30, died on Sunday, just six months after retiring from the game. She was diagnosed with liver cancer in January.
She and Mrs Murray remained close and worked together in recent years through Murray's role as captain of Great Britain's Fed Cup team.
Murray, who is mother to Wimbledon champion Andy and doubles player Jamie, was also a patron of Baltacha's academy in Ipswich.
In a statement she said: "I don't have the words to say what an incredible person Bally was, how loved she was or what an inspiration she will continue to be to everyone who met her.
"This is an awful loss for tennis, for all of us who knew and loved her but most of all for Nino and her family. My thoughts are, of course, with them.
"She was one in a million. An absolute gem."