In the first round of the 2015 UK Championship, Duffy pulled off a huge shock by eliminating world number nine and two-time winner of the event Ding Junhui 6–2. He credited the win to working hard on his game at the academy in Sheffield. He forced a deciding frame against Joe Swail in the next round having been 5–3 down, but lost it. He qualified for the China Open by beating Thepchaiya Un-Nooh 5–3, but would later withdraw from the event. Duffy lost in the final round of the EBSA Qualifying Tour Play-Offs to Sam Craigie, but by twice losing in the fifth round of Q School he earned a two-year tour card via the Order of Merit.