The Charles Fipke-owned colt hasn't raced since finishing sixth in the Prince of Wales Stakes at Fort Erie on July 13.
The one-mile Vice Regent will be the homebred's first attempt over the E.P. Taylor Turf Course.
"It's a distressing thing for a horse to have his oxygen cut off. We did a myectomy (throat surgery) on him. He didn't miss any time, but we backed right off on him," explained Attfield. "He's been working very well on the turf."
Not Bourbon, who will be piloted by Jono Jones, worked five furlongs on Aug. 22 over the backstretch turf training course in :59 3/5, breezing, on the outer portion of the oval.
The chestnut son of Not Impossible, is a full brother to turf sensation Perfect Soul, seeks his fourth stakes score of the season. In addition to winning the Plate by a head, he also won the Queenston and Plate Trial Stakes.
A victory in the Vice Regent, which is slated for race seven on Sunday's 10-race program, would push Not Bourbon's career earnings over the $1 million plateau.
VICE REGENT STAKES
POST - HORSE - JOCKEY - TRAINER
1 - Not Bourbon - Jono Jones - Roger Attfield
2 - Cappal Mor - Jim McAleney - Dan Vella
3 - Sand Cove - Slade Callaghan - Roger Attfield
4 - Piper in the Glen - Chantal Sutherland - Zeljko Krcmar
5 - Delaforce - Dave Clark - Nicholas Gonzalez
6 - Rockglen - Emile Ramsammy - Josie Carroll
7 - Eolos - Robert Landry - Deborah England