Japan head coach Jamie Joseph believes the Brave Blossoms have proven they can challenge the top nations at the 2023 Rugby World Cup despite a "disappointing" 20-15 loss to France in Saturday's second test.

Fabien Galthie's Six Nations Grand Slam winners completed a 2-0 sweep of the test series but were pushed to the brink at Tokyo's National Stadium by a young Japan side who led 15-13 with less than 10 minutes remaining.

Among the standouts for the hosts was 21-year-old flyhalf Lee Seung Sin, who marshaled the Japanese attack alongside 24-year-old scrumhalf Naoto Saito.

"We're a new team and we're really excited for the potential of this team," Joseph said.

Japan national rugby team head coach Jamie Joseph (C) shakes flyhalf Lee Seung Sin's hand after the Brave Blossoms' 20-15 loss to France at Tokyo's National Stadium on July 9, 2022. (Kyodo)

"I think the biggest learning for us as a team now is that our game is good enough, when we prepare properly."

Both sides committed multiple errors in the second half, but Japan's defensive lapse on France's 71st-minute try and a later fumble across the try-line ultimately prevented a maiden victory against the three-time World Cup runners-up.

"We made a lot of mistakes, obviously, in the second half, but we felt as a team we still put ourselves in a position to win the test match," former All Black Joseph said.

"I guess we have to look at the game in those moments, those small mistakes, the (lineout) throws the knock-ons."

Ryohei Yamanaka (front) of Japan scores a try during the first half of a rugby test match against France at the National Stadium in Tokyo on July 9, 2022. (Kyodo) ==Kyodo

While his players were disappointed at losing a game "they deserved to win," Joseph said the test series provided invaluable lessons.

"I think with some of our younger guys, our No. 9 (Saito), our No. 10 (Lee), experiencing that type of rugby...those kind of things are going to hold us in good stead going forward," he said.

The Brave Blossoms will take another crack at Les Bleus on Nov. 20 in Toulouse, on what is likely to be their final European tour before the World Cup hosted by France.

"The World Cup is sneaking up on us, (but) having said that, there's still plenty of time," Joseph said of the tournament that will be played in September and October of 2023.


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