Ruben Castro Martin sometimes known as just Ruben, is a Spanish professional footballer who plays for Real Betis. His profile is that of a striker. Castro was signed by Deportivo de La Coruña from local UD Las Palmas in 2004. Ruben scored his first goals for Las Palmas in La Liga in the 2001–02 season.At the beginning of 2006–07 Castro was on loan at Racing de Santander. During the January transfer window another loan happened, this time to Catalan side Gimnàstic de Tarragona.Ruben was loaned again in July 2008, to newly-promoted second division side SD Huesca. There, his goals proved crucial as the modest Aragonese outfit retained its recently obtained second level status. In August 2010 Ruben was sold to Real Betis, for a fee of €1.7 millions. On 27 August 2011, Castro scored his first goal in the competition in nearly four years, in a local derby against Granada CF. On 10 December 2011, Ruben put a stop to a streak of 11 games without one win for the Pepe Mel-led side. He finished the season with 16 goals – third-best national scorer, eighth overall – as the Verdiblancos finally finished in 13th position.