Having drawn with Barcelona at the Santiago Bernabeu on Wednesday, Blancos seemed jaded as they went down to an own goal from Cristiano Ronaldo on Saturday, with their hosts failing to register a single shot on target in the match.
The loss means that the Catalans can go 18 points clear of Madrid if they beat Valencia on Sunday evening, and Atletico Madrid can extend their lead over their neighbours to seven points should they beat Betis.
Ramos took to Twitter to say how everyone associated with the club was hurt by the loss, but added that the players would keep fighting for success.
"All Madridistas are feeling wounded today, above all the players," wrote the defender.
"But we are not going to give up on any competition, we will keep on going, for our badge and for our fans. Hala Madrid!"