A big filly that has been given time to mature, she has now had eight starts for three wins and a second with more wins in store.
Girl Sunday is the first winner for stakes-winning Cape Cross (IRE) mare Pleasantsundaygirl, a grand-daughter of Group III winner Furama Nights.
Also breaking his maiden at Morphettville on Cup Day was Rebel Raider three year-old Guns Loaded, who scored over 1600 metres for the Leon Macdonald and Andrew Gluyas stable.
A homebred for Harry Perks, Guns Loaded is the first winner for Commands mare Languid, a full sister to stakes-winner Moderate.
Languid has been a regular partner for Rebel Raider and also has a two year old colt and yearling filly by the dual Derby winner.