[2] After attending coaching sessions with the charity diversionary initiative 'Moving The Goalposts' as a child,[3] Hay began playing at youth level for Glasgow City at the age of 11.
[5] In March 2016, she scored her first senior team goal in the Scottish Women's League Cup against Inverness City.
[8] Having recovered from a serious ankle injury to be voted the league's Player of the Month for August/September 2019,[9] she agreed an 18-month professional contract extension with Rangers in December 2019.
[15] In September 2015 she scored two goals, within three minutes, against the Republic of Ireland at Ainslie Park; Scotland won the game 3–0.
[16][17] In 2017 she was part of the Scotland under-19 squad which qualified for the 2017 UEFA Women's Under-19 Championship,[18] and made one appearance at the finals tournament as a late substitute in a 1–0 loss to Spain.