Additions
| from | Name | Pos | Team | Team | ||
|---|---|---|---|---|---|---|
| 06/2018 |  | Joseba Ituarte | GK-CO |  | Muangthong United | Muangthong Utd |
| 05/2018 |  | William de Camargo | DF |  | CD Leganés B | CD Leganés B |
| 02/2018 | | Gabri | FW | | CD Leganés B | CD Leganés B |
| 01/2018 |  | Yahya Al Shehri | MF |  | Al Nassr | Al Nassr |
| 09/2017 |  | Nordin Amrabat | FW |  | Watford FC | Watford |
| 09/2017 | | Naranjo | FW |  | KRC Genk | KRC Genk |
| 08/2017 |  | Darko Brašanac | MF |  | Real Betis | Betis |
| 08/2017 |  | Claudio Beauvue | FW |  | Celta de Vigo | Celta de Vigo |
| 08/2017 | | Jaime Sierra | MF |  | Valencia CF U19 | Valencia U19 |
| 08/2017 |  | Ezequiel Muñoz | DF |  | Genoa CFC | Genoa CFC |
| 07/2017 | | Eraso | MF |  | Athletic Club | Athletic |
| 07/2017 |  | Owusu Kwabena | FW | |||
| 07/2017 | | Mauro Dos Santos | DF |  | SD Eibar | Eibar |
| 07/2017 | | Cuéllar | GK |  | Sporting Gijón | Sporting Gijón |
| 07/2017 | | Gallardo | DF | | CD Leganés B | CD Leganés B |
| 07/2017 | | Joseba Zaldua | DF |  | Real Sociedad | Real Sociedad |
| 07/2017 | | Raúl Carnero | DF |  | CD Alavés | Alavés |
| 07/2017 | | Gumbau | MF |  | FC Barcelona B | Barcelona B |
| 07/2017 |  | Leonardo Rocha | FW |  | AS Monaco U21 | Monaco (CFA) |
Departures
| from | Name | Pos | Team | Team | ||
|---|---|---|---|---|---|---|
| 01/2018 | | Leonardo Rocha | FW |  | Ontinyent CF | Ontinyent CF |
| 09/2017 | | David Timor | MF |  | Girona FC | Girona |
| 09/2017 | | Owusu Kwabena | FW |  | Real Oviedo | Oviedo |
| 08/2017 | | Sergio Segura | DF |  | CDA Navalcarnero | CDA Navalcarnero |
| 08/2017 |  | Marco Arcaleni | MF |  | Modena FC | Modena |
| 07/2017 | | Iu Ranera | MF |  | CF Peralada | CF Peralada |
| 07/2017 | | Diego Barrios | GK |  | UD SS Reyes | Sanse |
| 07/2017 | | Iago Herrerín | GK | | Athletic Club | Athletic |
| 07/2017 | | Adrián Marín | DF |  | Villarreal CF | Villarreal |
| 07/2017 | | Álvaro | DF |  | Alcobendas CF | Alcobendas CF |
| 07/2017 | | Pablo Insua | DF |  | FC Schalke 04 | Schalke |
| 07/2017 |  | Darwin Machís | MF |  | Granada CF | Granada CF |
| 07/2017 | | Rober Ibáñez | MF |  | Valencia CF | Valencia |
| 07/2017 | | Unai López | MF | | Athletic Club | Athletic |
| 07/2017 | | Alberto Bueno | FW |  | FC Porto | FC Porto |
| 07/2017 | | Luciano | FW |  | Corinthians SP | Corinthians |
| 07/2017 | | Samuel | FW |  | Rubin Kazan | Kazan |