De Gea allowed a shot from Cristiano Ronaldo to slip through his grasp, with the Real Madrid superstar completing his hat-trick with a spectacular late free-kick to claim an unforgettable 3-3 draw in Sochi.

De Gea is regarded as one of the world's best, but also made an error in a warm-up game against Switzerland, costing his side victory.

Spain captain Ramos is in no doubt De Gea should remain in goal for Spain's next game, against surprise Group B leader Iran in Kazan.

"It's not about never failing, it's about never giving up," Ramos wrote on Twitter, alongside a photograph of him embracing De Gea.

“Always on my team, [David de Gea]. Let's keep it up."

Speaking after the game, De Gea sought to play down his surprise error.

"I like that there are criticisms," he said. "Diego Costa has also been criticised and he scored two goals.

"I haven't killed anyone, either. I'm happy with the national team."