The France captain gave a frank assessment of the semi-final defeat, speaking to M6 after the final whistle, with goals from Mikel Oyarzabal and Pedro Porro sending Spain through instead.
"I think we didn't play the match we wanted to play. Whether tactically or technically, in the overall level we produced. And when you don't do what you're supposed to do in a World Cup semi-final, you don't win.
"Spain stuck to their plan and to what they're known for. They're a team that likes to control the ball and the tempo. Our aim was to press them high up the pitch so we didn't let them settle into that false rhythm. Because in terms of controlling the game, they're better than us. We didn't manage to do that, and there were too many technical mistakes. We didn't manage to hurt them when we needed to. It was up to us to change that balance of power and that's where we failed. Everything else is a consequence of what I've just said."
Asked for his tactical reading of the game, Mbappe pointed to France being repeatedly outnumbered in midfield.
"At the start, we kept finding ourselves in a three against two in midfield. And against Spain, that's difficult. Fabian (Ruiz) and Rodri had a lot of time on the ball. There was a lack of communication over the pressing. I think against Spain, we needed to play man for man, force them to run with us. And even when we did win the ball back high up the pitch, our first touches weren't worthy of a World Cup semi-final. And when you put all that together, it adds up to a defeat. It's a huge disappointment of course, but if we're honest, we didn't bring all the ingredients needed to reach the final."
On his own feelings after the final whistle, Mbappe admitted the scale of the disappointment was hard to put into words.
"Like everyone, I'm hugely disappointed. It was a dream for us to reach the final, to give our country the chance to keep dreaming and to make history. Now it's something we have to face head-on. I don't think I can really put into words how disappointed the group and I are. But like any top-level player, even if it sounds a bit robotic, we'll have to pick ourselves up, go on holiday and move on to something else. Because football waits for no one, we'll have to learn from it and move forward, putting this failure behind us."
France's World Cup campaign ends in the semi-finals, with Spain progressing to face the winner of the England v Argentina semi-final on Wednesday.