The 2010 champions got off to a dreadful start as they suffered a 5-1 defeat at the hands of eventual group winners the Netherlands, before falling to a 2-0 loss against Chile.
That result saw them eliminated from the competition, but they did at least save some face with 3-0 win over Australia in their closing fixture.
And, after returning to his homeland, Real Madrid vice-captain Ramos took to Twitter to make a promise to Spanish supporters.
"Falling isn't important, what is is knowing how to get up," he tweeted. "We'll bring you back the pride of feeling like champions."
Spain's UEFA Euro 2016 qualifying campaign kicks off against Macedonia on September 8.
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