Brought up in Stewarton in East Ayrshire, Scotland, Reilly began her footballing career at age seven with local boys" club Stewarton United and at one point attracted the interest of scouts from Glasgow side Celtic, She made her debut for the women"s side Stewarton Thistle Ladies in 1965 against the Johnston Red & White Rockets. She also competed in Hughie Green"s Women"s Football Tournament reaching the regional final, she was also part of the Stewarton side which lifted the inaugural Scottish Cup in 1971 and reached the first Word Federation of Advertisers Cup final the same year. Westthorn also reached the Word Federation of Advertisers Cup final losing 2–0 to Southampton.
A desire to play football professionally saw Reilly to move to French professional ladies" side Reims in 1974.
The Scottish Women"s FA had reacted to criticism from Reilly and two other players, Edna Neillis and Elsie Cook, by banning them sine die. Following on from her initial spell with Milan, Reilly continued to play in Italian football until the age of 40, including spells with the ladies" sides of Catania and Lecce.
lieutenant was the American team"s first ever appearance at international level