The Spanish central defender, who played top-flight football in Spain and Germany, will fortify the defence line of the Antonio Habas-managed side.
Rafa, a product of the Real Valladolid's youth system, represented club's main team as well as B team before moving on to SD Eibar in the second division.
In 2008, the defender joined Getafe CF, where finishing sixth to qualify for the UEFA Europa League in 2009-10 season was the highlight of his stint.