Illustrious Son, the 3-2 favorite, led from gate to wire in winning Gulfstream's sixth race to start the Rainbow 6.
The carryover coming in was $170,841.93. Bettors added $91,640 to the Rainbow 6.
Illustrious Son won in 1:23.15 on the dirt track listed as sloppy, in the $48,000 maiden special weight race for 4-year-olds and up.
Edgard Zayas rode for trainer Gilberto Zerpa and owner Gelfenstein Farm.