 In 1944, Kopf was named head coach of the Boston Yanks.This job was supposed to be temporary until Jim Crowley returned from the Navy However, instead of coaching the Yanks, Crowley became commissioner of the new All-America Football Conference and Kopf remained as the Yanks head coach until 1946.In his three seasons with the Yanks, Kopf had a record of 7–22–2.