Spanish centre-back Miguel Rubio, 28, is one of several Espanyol players who could be sent on loan to Castellón as part of the ongoing negotiations for Álex Calatrava. According to Esports Cope, the idea of including a loaned player has emerged as a way to facilitate the Calatrava deal, potentially speeding up the process and reducing the transfer fee. Rubio joined Espanyol in July 2025 and has a contract until 2028. He made 12 appearances and scored one goal in LaLiga last season. His current market value is listed by Transfermarkt as €1.50m. Real Oviedo has also been linked with the player.