The Widden Stakes has thrown up the past two Golden Slipper winners in Overreach and Mossfun but trainer Gerald Ryan is in no hurry to commit Fireworks to a start in the world's richest race for two-year olds.
Ridden by Brenton Avdulla, Fireworks settled well back in the field and still had three quarters of the field ahead of her inside the 300 metres.
The daughter of Snitzel charged home to defeat the stylish Fastnet Rock filly Lake Geneva by a long head with Denman filly Igraine a neck back in third.(photo Steve Hart).
"Early on we thought she was a little jump and run filly," Ryan said.
"A little bit of time you will see a lot of improvement, she still has a lot of growing and strengthening up to do.
"She has been a filly who is backward and is not entered in any of the big races because of that.
"I didn't get her until the end of September and John Camilleri said see what you can do with her and she has jumped out of the ground this time in.
"I know on Monday I'd like to put her on a float and send her out for a couple of weeks and freshen her up and let everything settle down before I decide what to do with her."
Fireworks becomes the fourth stakes-winner out of the Varick mare Calvinia following the Canny Lad filly Calveen, whose six group wins included the Group 1 Easter Handicap, then the Group II Emancipation Stakes winner Kosi Bay (Spinning World) and Listed winner Striker (Van Nistelroy).
Calvinia has a yearling Sepoy colt, who will be heading to the Easter Yearling sale, but has missed to that stallion in the past two seasons.
Fireworks is the 27th stakes-winner for Arrowfield Stud's hugely popular Snitzel who covered over 200 mares for the third consecutive season in 2014.
