Sergio Ortuño Díaz (born 2 March 1999), sometimes known as Ortu, is a Spanish professional footballer who plays as a midfielder for CD Eldense.

Born in Elda, Alicante, Valencian Community, Ortuño finished his formation with Deportivo de La Coruña, after representing Hércules CF and CD Eldense.

He made his senior debut with the former's reserves on 15 October 2017, coming on as a second-half substitute in a 3–0 Segunda División B home win over CF Talavera de la Reina.

Ortuño was promoted to farm team Laracha CF in Tercera División ahead of the 2018–19 season,[1] but was loaned back to former club Eldense on 21 December 2018.

[4] On 25 January 2022, he agreed to a 18-month deal with Real Valladolid's reserves in Primera División RFEF,[5] but returned to Eldense on loan on 14 July 2022.