Lining up against the likes of Buddy Be Cool, Egotistical, Mosquito Squad and Flying Annie, Oh So Smooth was unwanted by punters at $14.20 but belied the odds with an all-the-way triumph.
He jumped straight to the lead from box four and held that position throughout the race.
He withstood a late challenge from Egotistical in the closing stages and held on to score by a neck in 22.50 to record his 16th career win.
In other races, a brilliant start from Timmy Fields carried that greyhound to an impressive victory in the Silver Sands Resort Bridge Stake (405m).
Timmy Fields exploded from the yellow box and shot away to a convincing lead before crossing the line five lengths ahead of veteran chaser Black Mandagery in a time of 22.83.
The Kevin Foxton-trained race dog has now saluted in six of 23 starts.