Their build-up to the World Cup was rocked when coach Julen Lopetegui was sacked two days before their opening game against Portugal when he agreed to become Real Madrid manager.
Fernando Hierro took charge and the Spanish were viewed as among the favourites to lift the World Cup after winning Group B and entering the half of the knockout draw without the likes of Brazil, France, Belgium and Uruguay.
However, they lost on penalties to Russia despite making more than 1,000 passes in a game where they dominated possession but never threatened on a regular basis.
Following this game, Ramos wrote an open letter that was published in Spanish newspaper Marca, in which he also insisted that the team could not have done any more to try to beat Russia.
Ramos said: ‘It was an immense, exciting challenge that we faced with all the energy of the world. And when we had not yet started, something happened that we did not expect. I will not value acts or decisions, but instability is never a good companion.
‘Even so we maintained the cohesion, the strength of the group, the energy of a group of colleagues and friends, but the truth is that we have gone from more to less. Although many think we could have done more, we did not know how to do more.
‘We could do better, we should have done better, but not only I’m not ashamed, I’m proud to be the captain of this huge selection.’
Ramos also paid tribute to international team-mate Andres Iniesta, who retired from international football following their World Cup exit.
He said: ‘A special reminder for a friend in adventures and misadventures, that made us feel what we never imagined. Iniesta, it has been a pleasure to walk this road with you in red. I wish you could have taken a better memory for your farewell.’