The Florida-bred sophomore posted an upset in the seven-furlong event, winning by a head at odds of nearly 14-1.
"He looks good this morning," Machowsky said. "He ate up last night and everything appears to be okay with him."
The son of Halo's Image will now be considered for either the Sunshine Millions Classic on Jan. 24 or the Strub Stakes (gr. II) for fellow 4-year-olds on Feb. 7.
"He's the kind of horse we're only going to be able to get five or six races out of a year," Machowsky said. "It was a tiring track yesterday and you've got to think that race took something out of all of them. So he won't make the (Jan .10) San Fernando (gr. II) because it's too quick back for him, but the other two races are far enough out.
"If we run him in the Sunshine Millions it would be about money and if we run him in the Strub it would be about prestige. I'll have to talk it over with the owners before we make a decision. I'm really happy for them. It's been hard and very frustrating and aggravating with this horse because just as he was getting ready, something else small would come up and we'd have to back off on him. It was hard for the owners' and me to keep the faith sometimes, but it was worth it."
Overall Southern Image has won three of four career starts, with a third in last year's San Vicente Stakes (gr. II), for earnings of $231,600.