Romanian Fed Cup captain Ilie Nastase's presence at the Madrid Open trophy presentation ceremony was "irresponsible and unacceptable", said the head of women's tennis.
Nastase, 70, is under investigation by the International Tennis Federation (ITF) following his behaviour at last month's Fed Cup tie with Britain.
However, Nastase shared the stage with Madrid champion Simona Halep on Sunday.
"He had no place on the court today," said WTA chief Steve Simon.
Nastase, a former French and US Open champion, was ejected from the Fed Cup tie in Constanta after abusing British player Johanna Konta and captain Anne Keothavong.