France coach Jacques Brunel offered no defence for Sebastien Vahaamahina after his red card helped Wales to a 20-19 World Cup quarter-final win.
Vahaamahina was dismissed in the 49th minute for elbowing Aaron Wainwright in the head. France led 19-10 at the time and were 10 metres from the Wales line.
"I don't contest it," said Brunel of the red card.
"When you see the image it is clear. It was a reflex and we cannot deny he had contact with his face."
With the man advantage, Wales clawed their way back and finally took the lead in the 75th minute via a Ross Moriarty try and Dan Biggar conversion.
Brunel questioned whether the ball had gone forward in the build-up to that decisive score when replacement scrum-half Tomos Williams ripped the ball free of French hands.
"There are other decisions I don't agree with," added Brunel, when asked about referee Jaco Peyper's performance.
"I think the scrum at the end on which we pushed a little, we lost the ball - I would like to see it again.
"The last try, there is a player who pulled on the ball and it went forward and so that's the decision I would like to see again because I am a little disappointed.
"Of course the red card changed the match. In a quarter-final playing for half the match with 14 men it is difficult but I want to stress the quality of our team which showed courage."
Brunel is set to be replaced as coach by Fabian Galthie after the tournament and he believes his successor has a strong foundation to build towards the 2023 tournament that France will host.
France won the 2018 Under-20 World Championship with a team that included fly-half Romain Ntamack.
"For the future generations we are one of the youngest teams in the competition, and all the potential. They will keep on learning and it will make them mature. There is a brighter future for this team," he added.
Analysis
Former Wales international Tom Shanklin on Radio 5 Live
Vahaamahina's red card was inexcusable. It was aggression, he knew exactly what he was doing and there are no excuses. He lost that game for his team. It's just stupid. If you're a French supporter, a French player... it is one of the worst things I've seen."