A goal from Bradley Barcola after 12 seconds was a nightmare start, made even worse by the manner Italy conceded, with defender Giovanni Di Lorenzo allowing the French forward to steal possession instead of dealing with a simple back pass.
"The start was the key, everyone reacted immediately, trying to give strength and tranquillity to the team and then they played the game we needed to play, so doubly good," Spalletti told RAI after the final whistle.
"It was important to remain as a team, beyond the initial misfortune, because with so much tension, any situation can reduce you to madness.
"That's why our mental strength was double, because the things that happen to you come from your head, your fears and from what you think you can't achieve."
It was an altogether different Italy to the one seen at Euro 2024, when they put up a feeble attempt at defending their title, winning only one game and going out to Switzerland in the round of 16, and Spalletti praised his squad who won in Paris.
"We chose a group of players who are always in the game. They are a little fresher than they were at the end of the season," Spalletti said.
"Probably we were lucky to find a bunch of young players eager to prove themselves. Individual desire and passion are the keys to any success."
Goalkeeper and captain Gianluigi Donnarumma barely had time to notice the game had started before he was picking the ball out of the net, and he too praised his team's ability to recover.
"I wasn't ready yet, I hadn't even put on my glove," Donnarumma said.
"We weren't too clever because the ball was ours, we could have waited. But we did well to react afterwards.
"Conceding a goal so early was tough but the guys were able to remain calm, focussed on doing what we tried in training and playing the ball well, and that was essential to winning the game."