In the Champion Stakes at Ascot on 14 October he produced an improved effort, briefly taking the lead in the straight before finishing fifth behind Almanzor, Found, Jack Hobbs and My Dream Boat. In January 2017 The Grey Gatsby was transferred to the stable of Dermot Weld in Ireland. He failed to recapture his form, finishing no better than fourth in six races, and was retired at the end of the year. In the 2014 World's Best Racehorse Rankings, The Grey Gatsby was rated the third-best horse to race anywhere in the world in 2014 behind the Japanese horses Just A Way and Epiphaneia and level with Able Friend, Australia, Kingman and Variety Club. He was the joint top-rated horse in the Intermediate distance division and the joint top-rated three-year-old. The Grey Gatsby began his career as a breeding stallion at the Haras du Petit Tellier in France.