The England manager expressed his regret over the errors that allowed Spain to come back at Wembley, insisting that "at this level, the details matter".
Spain beat England 3-2 on Saturday evening in the opening round of League A fixtures in the UEFA Nations League, after Tuchel's side failed to preserve the 2-1 lead they carried into the break.
Tuchel explained why he left Trent Alexander-Arnold out of the starting line-up, and said England must learn from the defeat before they face the Czech Republic in Prague.
He added after the match, according to the Spanish website okdiario: "We faced the best team in the world, but we made a lot of mistakes, especially in the first ten or twelve minutes, and in the attack that led to the equalising goal".
England put in a "very good performance" in the first half and the start of the second, Tuchel believes, and he stressed: "Against an opponent like this, you have to take your half-chances. In the final third of the pitch, we lacked execution and calmness".
The England manager continued: "We wanted to be the ones to beat them, and we felt we were capable of that between the halves, and because of our performance in the second half. But we lost".
Spain, he confirmed, "were calmer and more precise in turning our mistakes into clear-cut chances".
A model for success?
Tuchel refused to regard Gordon's goal as a model of England's way of achieving success, saying: "No, the goal came from a counter-attack", according to the Mirror.
He explained: "If you want to call it that, it was a winning of the ball and a superb transition attack. We scored stunning goals, and we could have created more had we been more decisive in the last 20 metres".
He added: "The effort put in without the ball is also part of our identity, and the boldness and courage in winning back the ball in advanced areas were exceptional. I think we won back around 12 or 15 more balls than Spain in their own half, but we could not convert enough of them into chances and goals, otherwise we would have won the match".
Trent's absence
Tuchel justified keeping Trent Alexander-Arnold on the bench, saying that "the match required a great deal of defensive effort, so he gave priority to the speed and the ability of the chosen full-back to also play as a centre-back when England play with three defenders".
Asked about Lewis Hall, he said he did not want to take a risk after the player missed training earlier in the week due to feeling unwell... he will be given other opportunities, we have three matches remaining".
On the upcoming Czech Republic match, he concluded: "Pointing out each player's mistakes individually and advising them not to repeat them will not help. The mistakes were many, but there are positives to build on. We need the points, and we want to qualify".