Mercedes Paz won in October 1984 in Tokyo at her first tournament as a professional player on the WTA tour the first title (double ). Previously, she had participated with the Argentine team in the Olympic Games in Los Angeles, where she lost her opening match but in singles.
She won in her tennis career total of three singles and 22 doubles titles on the WTA Tour. At the end of her career she was still playing on the ITF Women's Circuit, on which they could celebrate another five doubles titles.
In 1998, she ended her professional career. In September 2002, she appeared one more time in an ITF tournament; they failed in women's doubles in the first round of qualifying and left it at that.