Following the end of his career with Connacht, Duffy expressed an interest in taking up Gaelic football again. Having lived in Galway during his career with the province, Duffy took up football with the local team Salthill-Knocknacarra, who he had occasionally played with during his rugby career. He was then called up to train with Mayo's senior team by manager James Horan. Duffy was reportedly a 'stand-out performer' in training and was added to the panel. Horan later said that although Duffy's skill-set was "a bit off where it needed to be", the management team were "very excited about where he is and how it's progressing".