SHANGHAI -- It should've been a forgettable game, just a formality in pool play. But Jayson Tatum always remembered the big athletic guy on Team Japan.

It was four years ago in Dubai, and Tatum was playing for the U.S. team in the under-17 world championships. He had a nice game, leading the team with 19 points as it beat the Japanese by a preposterous 122-38 margin.

But of those 38 points, a lanky and fluid young kid named Rui Hachimura scored 25 of them. The Japanese went a woeful 1-6 in the event, but Hachimura was a revelation to Tatum and many who were there. He averaged 22.6 points and 6.6 rebounds, the leading scorer of the tournament.

"It's funny, I always remember that game," Tatum said this week as he played in his first World Cup in China, now all grown up just like Hachimura. "He definitely stood out from the other guys. It's no surprise that he's at where he's at today."

Today, the 6-foot-8 Hachimura is a rising rookie with the Washington Wizards, picked No. 9 overall in June's draft after a standout career at Gonzaga. On Thursday, he will play the U.S. again as the teams close pool play.

Hachimura probably won't play a lot, with Japan having been eliminated from advancing to the next round. Tatum won't play at all after spraining his ankle against Turkey on Tuesday. But the Wizards' prized prospect has gone from a nice little story for scouts in the Middle East to a full-fledged sensation in the Far East.

This has been a remarkable summer for Hachimura, hinting that he may make a splash when he reports for training camp in D.C. later this month. Two weeks ago, he scored 31 points in front of 18,000 fans at the Saitama Super Arena outside Tokyo as the Japanese, ranked 48th in the world, pulled off an upset against Germany in an exhibition game.

Wizards' lottery pick Rui Hachimura has energized Japan's national basketball program. Kazuhiro NOGI/AFP/Getty Images

To put it in perspective, the Japanese have never beaten a European team in World Cup play. Hachimura's block on Dennis Schroder of the Oklahoma City Thunder in the closing minutes -- OK, it might've been goaltending -- was a signature moment.

It was part of a three-game series at the Saitama Super Arena, where the basketball events in next summer's Olympics will be played. All of the games drew more than 16,000 fans. The Toronto Raptors and Houston Rockets will play there in October as part of the NBA's Global Games preseason tour.

"A couple years ago when I watched the national team games, there were just a couple thousand people there," Hachimura said. "Now it's crazy."

Japan has been in a bit of a basketball depression. The NBA once viewed it as a vital market and played regular-season games there in the 1990s and as late at 2003. But when Michael Jordan retired, interest dimmed. The NBA ended up closing its office there as it shifted its attention in Asia to the bigger and more basketball-crazed China.

Japan's teams were pummeled on the international stage, and in the mid-2010s they were even suspended by FIBA for a time because of disorganization. But Hachimura is leading a renaissance along with Yuta Watanabe, who plays for the Memphis Grizzlies. For all of China's basketball growth and love, Japan may have a brighter future with two rising NBA players on its team.

"Rui is a generational talent for that country, and he will bring enormous attention to the sport," said Wizards general manager Tommy Sheppard, who spent two weeks in Japan and China bonding with his first draft pick as the head of the team's basketball operations. "He's going to be a fantastic player for the Wizards in the future. He has the ability to be a factor at both ends of the floor, [has] a solid basketball IQ and is a great teammate."

The opposition has swarmed Hachimura in this tournament, sending double- and triple-teams his way. He had 15 points and seven rebounds against Turkey and then 21 points, six rebounds and four assists against the Czech Republic. Considering that the Japanese play a lot of zone, it isn't a great representation of what he'll be doing in the NBA.

But his athleticism leaps off the court. Just like back in 2015 when he wowed the Americans, there is no doubt the skill set is there to be a difference-making player in the NBA.

"We're thrilled with his progress this summer," said Sheppard, who watched Hachimura score 23 points against Argentina in an exhibition game as well. Japan has an automatic bid into the Olympics as the host nation next year, removing some of the drama for qualifying at the World Cup. But just getting to this point was a success: Japan didn't even qualify to play in the 2014 World Cup.

"Basketball is growing in Japan," Hachimura said. "As players, we've got to show more results and show Japan basketball to the world."