 He made his Serie A debut on 16 September in Roma's 3–0 win over Hellas Verona, replacing Kostas Manolas in the 73rd minute.On 31 January 2018, Spanish club Real Sociedad announced the transfer of Moreno from Roma for €6 million, signing with the club until 2021.On 15 February, he made his competitive debut for "La Real" against Red Bull Salzburg in the Europa League, playing 76 minutes in the team's 2–2 draw.