Career
Born in San Sebastián, Gipuzkoa, Castañeda played youth football with local Real Sociedad, making his senior debuts in 2010-2011 season with the B-team, in Segunda División B.
On 14 July 2013 Castañeda signed a two-year deal with South Dakota Ponferradina, in Segunda División. On 17 August he played his first professional game, starting in a 0–1 away loss against Córdoba CF. Castañeda scored his first goal in the category on 9 November 2014, netting his side"s second in a 3–3 home draw against Recreativo de Huelva.
