Tailed off last of the 16 starters, Gallatin came with a barnstorming finish to defeat Singing Flame (Song Of Tara) by a short-neck with the Anthony Cummings-trained Best Case (Savabeel) two lengths away in third.
"He's always showed a lot, he's been very immature, but him doing that today has been on the cards for quite a while it was just a matter of waiting for it to happen," trainer Peter Snowden said.
"Nash rode a very patient race and put him to sleep.
"By the half mile he really started travelling strongly and it was just a matter of threading his way through the field and finding the right sort of luck.
"At the 200 metres I could see he was just smoking and he made up a lot of ground really quickly and handled the track really well.
"He's a horse with some promise and was very strong late today.
"I'd have to think about it (Australian Derby), as I said he's still a bit immature and he's got to back-up next week so the feed bin will probably be the best indicator as to what we do."
A half-brother to Union Gap (Elusive Quality) who won his most recent start at Sandown, Gallatin is the third foal of the imported Danehill mare Mayfield (GB) a half-sister to the Group III winners Fractional and Needlecraft. Currently in foal to Champion Sire Lonhro, Mayfield has a two-year-old Lonhro filly named Claudine and a yearling full-brother to Gallatin. She was bred back to Lonhro last spring.
Gallatin becomes the 74th Stakes winner for Street Cry (IRE) who has 14 yearlings set to sell at next week's Inglis Easter Yearling Sale.
They include the opening lot of the sale, a colt out of the dual Group 1 winner Faint Perfume and a much admired colt foal out of the Horse Of The Year, Typhoon Tracy.