France have the youngest squad in the World Cup knockout phase, but they made up for a lack of experience with raw talent and character as they came from behind to beat Argentina 4-3 in a last-16 thriller on Saturday.
Les Bleus' average age is 26 years old -- like England -- and Kylian Mbappe is 19, but it was he who ran riot after France fell 2-1 behind early in the second half.
Five players in France's starting line-up had never played a World Cup game before coming to Russia but debutants Mbappe and Benjamin Pavard found the back of the net when the team was in trouble.
"We were up against a highly experienced Argentine team but we showed we were there and the team showed they had character," Deschamps, who led France to World Cup glory as captain in 1998, told a news conference.
"When we were 2-1 down it was not easy but we kept fighting. The mentality in this group is excellent."
After opening the scoring with an Antoine Griezmann penalty, France looked too strong for Argentina, but they wasted chances to bury their opponents and were punished either side of the break.
Angel Di Maria benefited from the French defence's passiveness to equalise with a long-range cracker before Gabriel Mercado flicked Lionel Messi's shot past Hugo Lloris.
It was a moment of truth for France, who could have crumbled under a mix of fear and disappointment, but Deschamps was never worried.
"We couldn't miss it and we didn't miss it," said Deschamps, whose experience as a player and coach instils confidence in his squad.
"I'm not afraid, I'm not fearing anything. When this second (Argentina) goal was scored, it was a blow," he said.
"We could have equalised quicker with Antoine. As long as you have time, even if you have a highly experienced team in front of you, I know that the French team are ready to face it."
Pavard's stunning half-volley, which brought back memories of fellow full back Lilian Thuram scoring twice in the 1998 World Cup semi-finals, restored parity, and Mbappe's raw pace ultimately made the difference.
Although France must improve in defence after conceding three goals, they know they can score even more as they gear up for a quarter-final clash against a more robust team - Uruguay or Portugal.
"Even if we had less possession of the ball on some counterattack we could have scored more goals I think," Deschamps said.
Paul Pogba bossed the midfield with N'Golo Kante.
"Mentally, physically, technically, we showed we were a great France team today," Pogba said.
"We showed our qualities and we demonstrated that we could be there against the big teams. But we're not world champions. We'll be happy until tomorrow and then, back to work."