The shot stopper spilled a speculative shot from Cristiano Ronaldo late in the first-half of their opening match of the tournament, allowing Portugal to restore their lead before half-time.
Although La Roja recovered to go 3-2 up, Ronaldo struck again from a free-kick to complete his hat-trick and earn a draw for the Euro 2016 winners.
De Gea said he felt “calm” in the wake of his mistake , insisting “only those of us who put on our gloves and go out in the field know how hard [it is]” and quickly turning his attention to winning the next game.
And team-mate Ramos hopes his reassuring message will boost the Manchester United star’s spirits further as the fight for Group B’s top spot immediately heats up.
"It's not about never failing, it's about never giving up,” he tweeted.
“Always on my team, [David de Gea]. Let's keep it up.”
Ramos was not the only familiar face to give his backing to the 27-year-old, as United coach Jose Mourinho pointed out that any goalkeeper is at risk of committing such blunders .
No se trata de no equivocarse,
se trata de no rendirse nunca.
It's not about never failing,
it's about never giving up.
En mi equipo siempre, @D_DeGea
Always on my team.
¡Seguimos! / Let's keep it up. #VamosEspaña 🇪🇸 pic.twitter.com/SNizXiBW1Y — Sergio Ramos (@SergioRamos) June 16, 2018
“It's a mistake he doesn't make with us at Manchester United because he was named player of the season for fantastic performances,” he said on RT. "But that happens to the best."
De Gea will get the chance to bounce back in Spain’s next game, against Iran on June 20.