France's Antoine Griezmann said he forgot that the video assistant referee (VAR) was being used in the World Cup but praised referee Andres Cunha for making the right decision to award the penalty that set them on their way to a 2-1 win over Australia.
Griezmann was clipped by Joshua Risdon, but Cunha did not blow immediately and instead used technology to revisit the incident.
The France striker scored the spot kick, with Paul Pogba getting France's winner after Mile Jedinak had equalised from the spot and all the goals coming after the break.
"I thought it was a penalty," Griezmann told reporters at Kazan Arena. "However, after the referee did not blow his whistle, I forgot about VAR -- all the better for us [that it exists].
"When the referee went to check out the video, I already had the penalty [in my mind] -- I was focused on taking it."
Griezmann was voted man of the match, but said he felt teammates N'Golo Kante or Lucas Hernandez should have got the prize instead.
"The man of the match award is not the most important thing," he added. "I would have given it to N'Golo or Lucas.
Griezmann admitted that pressure surrounding the French team, with seven players out of the 11 starters having never played in a World Cup before, was intense.
"It was laborious and we didn't do well," he said in the mixed zone. "With the ball, we were not good enough. It was only the second time I was playing up front with Kylian [Mbappe] and Ousmane [Dembele]. We need more time to get used to play with one another.
"But I am not worried. It was the first game in a World Cup and it is always special. It is a lot of pressure especially for the new players. I still remember my first time four years ago. We want to do better in the next game against Peru which will be tougher."
Pogba, whose winner was aided by goal-line technology after his strike clipped a defender and bounced off the underside of the bar, told TF1: "It is the World Cup -- there are no small teams. Australia defended well. For my goal, I was helped by the defender. Scoring with your ear or your nose, not just your foot -- it does not matter as long as it goes in."
"I didn't expect such a tough game and to play against a team so well organised," he added in the mixed zone. "They were really determined and they defended very well. It was hard to play against them. We didn't create much. We have to stay positive.
"We have to play more as a team and respect those games. Our opponents always play deep against us and we need to find a way to play better in those kind of matches."
Coach Didier Deschamps told TF1 his players were capable of better, saying: "It was not easy, but winning the Group C opener was very important.
"It was complicated against a team that caused us problems. We got the job done, but we can do much, much better."
Defender Samuel Umtiti, who handled the ball to give Australia their penalty, thanked his teammates for helping him to put his mistake behind him.
"These things can happen in games. I was able to re-focus, thanks to my teammates, and focus on the win and the win only. Mistakes happen, you have to own them and the quickly move on," he said.
A sharp first-half save from captain Hugo Lloris prevented Australia from going ahead through a Corentin Tolisso own goal, and the Spurs keeper warned that France must do better.
"The whole team has to do more and better in the efforts we put in, in our intensity, in our pressing, in our passing game, in our energy on the pitch," he said in the mixed zone. "The Australians played very defensively.
"We had some luck to win but it was very important to start the tournament with a victory. I would rather play badly and win this game than play well and not win it. It is a step forward. Peru will be stronger than Australia and we will have to be ready and Denmark will be stronger than Peru too.
"We all have to raise our game now and step by step we need to build our confidence and our momentum."
Once again, France looked like they didn't play enough as a team and Lloris agreed.
"We all have to be on the same page. When 11 players are thinking the same football, it makes things easier," he added. "We have to find the right balance. We have to do better in how we control matches in the way we use the ball, in our positioning with and without the ball.
"Today, we gave the ball to the Australians too much and when we don't have the ball we are not comfortable."
Information from Julien Laurens was used in this report.