Disambiguation: Steve Rogers' WWII sergeant
First published in: 1941
Sergeant Duffy first appeared unnamed in Captain America Comics (Marvel, 1941 series) #1 (March 1941). He was called "Sergeant Duffy" beginning in Captain America Comics (Marvel, 1941 series) #4 (June 1941). He was named "Sergeant Thaddeus Duffy" in Captain America Comics (Marvel, 1941 series) #10 (January 1942). He was renamed "Michael Joseph Duffy" in Young Allies 70th Anniversary Special (Marvel, 2009 series) #1 (August 2009).