Mary Lou Piatek-Daniels (born August 6, 1961) is a retired tennis player from the U.S. who played on the WTA Tour during the 1980s.
In 1979, she was the no. 1 junior in the world. She won her first pro title at Richmond, Virginia 1981, beating Sylvia Hanika and Sue Barker en route. She was coached by her father Joseph, a former varsity player at Indiana University, and by Trinity coach Emilie Foster.
Piatek-Daniels made her ranking debut in February 1980 at no. 45. Her career wins include Robin White, Christiane Jolissaint, Kathy Horvath, Wendy White, Gigi Fernández, and Betsy Nagelsen.[1]