England's manager voiced his regret over the errors that let Spain fight back at Wembley, insisting that "at this level, the details matter".
Spain beat England 3-2 on Saturday evening in the opening round of top-tier fixtures in the UEFA Nations League. Tuchel's side had led 2-1 at the break but couldn't hold on.
The German explained why he left Trent Alexander-Arnold out of the starting line-up, and said England must learn their lessons before facing the Czech Republic in Prague.
Speaking after the match, he told 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 the execution and the composure."
He continued: "We wanted to be the ones to beat them, and we felt we were capable of doing that at half-time, and because of our performance in the second half. But we lost."
Spain, he admitted, "was calmer and more precise in turning our mistakes into clear-cut chances".
A model of success?
Tuchel rejected the idea that Gordon's goal was a blueprint for how England find success. "No, the goal came from a counter-attack," he told the Mirror.
"If you want to call it that, it is a ball won back and a superb transition attack," he explained. "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 balls back in advanced areas was exceptional. I think we won back around 12 or 15 more balls than Spain in their half of the pitch, but we could not convert enough of them into chances and goals, otherwise we would have won the match."
Trent's absence
Alexander-Arnold's place on the bench came down to the demands of the game, Tuchel argued, saying "the match required a big defensive effort, so he gave priority to the pace and ability of the chosen full-back to also play as a centre-back when the England team plays with three defenders".
On Lewis Hall, he said he did not want to take a risk after the player had missed training earlier in the week due to feeling discomfort. "He will get other chances, we have three matches remaining."
Turning to 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."