Japan erupted in cheers and tears after the national team's 2-1 win over Spain early on Friday, with crowds packing public viewing areas in the pre-dawn cold shrieking with joy as they stunned another global football power at the World Cup.
Japan, who had also shocked Germany in their opener in Qatar, finished top of Group E to reach the last 16, a stage where they have faltered three times before.
They will play 2018 runners-up Croatia for a place in the quarter-finals.
"I never thought Japan would advance first place in the group. Thank you Japan! I love you guys!" said 19-year-old Yusei Sato, wearing Japan's Samurai Blue national team jersey.
Takuya Kudo, 23, was in tears as soon as he saw Japan win.
"I'm just so happy," he said. "Honestly, I never thought Japan would do this well. I'm just really thrilled."
Fans lingering in Shibuya pressed high-fives on bleary commuters making their way to work from one of Tokyo's busiest stations.
Social media exploded with joy, exulting "Samurai Blue!" and "Came from behind to win!," with some fans posting manga-style drawings of a cheering player in a team uniform.
Another posted a cartoon of three dragons draped in national flags. The Japanese dragon was roaring while the Spanish dragon eyed Germany, which looked befuddled.
Japanese tennis player Naomi Osaka's tribute was a manga-style depiction of the Japanese team, while even Elon Musk tweeted, "Congratulations, Japan!"
The sense of triumph rose even to Japan's normally staid political heights, with Prime Minister Fumio Kishida telling reporters the win was "historic" and telephoning Japan coach Hajime Moriyasu and Japan Football Association President Kozo Tashima to offer congratulations.
"I told them they gave the Japanese people courage and energy," Kishida said on Twitter. "We are looking forward to the last 16. Fight on, Japan!"