[3][4] Duggan started his coaching career with Boston College as a defensive graduate assistant for one year.
However Moala would knock Duggan to the ground dislocating his elbow and fracturing his wrist.
[11] After one season with the Buckeyes, Duggan would return to Boston College as the team's linebackers coach.
[14][15] On January 31, 2024, Duggan's head coach at Boston College, Jeff Hafley, was hired by the Green Bay Packers to be their defensive coordinator.
[17] On February 3, 2025, linebackers coach Anthony Campanile was hired by the Jacksonville Jaguars to be their defensive coordinator.