Les Bleus struggled to contain the Japanese in a second-half spell in which John Kirwan’s side came back to within four points only for France to run in three late tries to seal the win.

And Lièvremont, who is also sweating on the fitness of Fabrice Estebanez and David Skrela who both went off injured, admitted the victory was the only positive to take from the game.

“I’ll take the victory, that was the most important thing for me and to start the competition,” said Lièvremont. “Other than that I wanted a consistent game and obviously in this regard I’m not satisfied.

“I was already not satisfied at half-time. We lacked ambition from the start. On our first four lineouts we started unproductive mauls with one player picking and going and getting easily stopped.

“We saw from the start that we had a very strong scrum with some positions in the centre of the pitch where we should have made the most of overlap opportunities but we wasted them.

“Despite everything we did at least open the scoring and were leading two tries to none, but after that we produced nothing. We didn’t play together.”

The way Les Bleus began the game gave no indication of their later struggles as Estebanez made a searing early break before Julien Pierre crashed over for the first try after just four minutes.

And they made it two soon after as François Trinh-Duc pounced on a James Arlidge pass to run in from inside his own half.

Dimitri Yachvili converted both tries and added a further two penalties while Arlidge opened Japan’s account with a penalty of his own.

Arlidge then had a slice of fortune as he tried a grubber kick which bounced back into his hands and he ghosted over to make it 20-8 on the half hour.

France reacted immediately with Cédric Heymans bursting into the line to release Aurélien Rougerie who found Vincent Clerc for his 26th test try.

Arlidge added another penalty before the break and after Lionel Nallet and Imanol Harinordoquy had both gone close, the Nottingham pivot burst through two tackles to score his second try of the day.

His conversion made the score 25-18 and after another penalty France were looking very nervous.

But with ten minutes to go they finally sealed their bonus point fourth try through Lionel Nallet before two long-range efforts from Pascal Papé and replacement Morgan Parra gave the score a flattering gloss.