Philippe Saint-André believes France are not far from the world's best despite their defeat to England at Twickenham.
Les Bleus conceded a half-century for the first time against northern hemisphere opposition, going down 55-35, but they were much better in attack than in previous weeks.
Scoring five tries in total, France could have been closer, but missed 12 points from the kicking tee, while they struggle to cope with the rhythm imposed by the English.
But despite a 20-point winning margin, Saint-André feels his side showed that they are getting closer to the top teams with no more competitive matches left before the World Cup.
"We're not far from the best teams in the world. I told the players that the World Cup starts tomorrow," he said.
"They are going to have to put in the work. But they need to keep this mindset. International rugby at the highest level is almost another sport. If you can't see that, you die.
"We need to be more lucid, and have more control. We need to be able to cope with actions that last three minutes and still be in place defensively. We have a squad that is 150% behind the project.
"It takes time for it to work and come to fruition. We aren't going to play two nothing friendlies. We'll play the English twice because if you want to be world champions you have to play the best teams in the world.
"It was a great match of rugby and the French players were great. It was an incredible, fantastic match. But we lacked a little control and a lot of lucidity. Especially on the first try where we give them seven points after 90 seconds.
"We also must have left 15 points behind with the boot (it was 12) and if we'd got some of them, the game might have gone differently. We knew the English wanted to win the Championship and were going to play at pace. We also came to play rugby and it made for a great game.
"I think we saw the character of the team in Rome. It was a difficult, yet important game. Today it was a very high-quality game with pace, intensity, technique and a battle. We know that we have to improve our reactivity. We played a lot of rugby but as soon as we lost the ball we were punished. We know what we have to work on from July 6th looking towards the World Cup.
"The players gave everything this evening, they showed some good things. We have to improve in some areas of the game to have a big World Cup. It's the sort of match that helps you grow. But we struggle to ram home our advantage. The little errors are costly."