AL RAYYAN, Qatar – A Japanese flag danced in the gentle breeze at the Khalifa International Stadium on Thursday night.

Held up by a member of the Ultra Nippon, it was a serene moment that felt a little surreal given the incredible scenes that had played out just moments earlier.

The group of Japanese diehards, about 100 strong, was among the last of the close to 45,000 fans who had watched Japan’s sensational 2-1 win over Spain to shuffle out of the stadium.

“It was amazing,” blond-haired Shinjiro Shide said, voice hoarse from all the singing and cheering. “This was (football) history’s No. 1 game.”

The Samurai Blue upset 2010 winners Spain, having beaten 2014 champions Germany by the same scoreline and at the same venue, eight days earlier. In both games, they trailed and fought back with goals in the second half.

In between those famous wins, Japan slumped to a 1-0 loss to Costa Rica.

Thursday night’s result meant Japan topped Group E ahead of Spain, who join them in the knockout phase. Four-time champions Germany suffered a second consecutive World Cup group-stage exit.

“I still don’t know how we lost to Costa Rica,” said another fan, Shunji Kondo, with a chuckle, as the Japanese flag draped over his shoulders like a cape fluttered in the wind. “But to beat Spain and Germany.... I can’t believe it.”

The Ultra Nippon, armed with their flags, banners and drums, have provided the soundtrack to their team’s giant-killing feats.

The Japanese supporters in general, have also endeared themselves to locals and visiting fans with their costumes, and with their habit of staying behind after games to pick up trash from the stands.

At the full-time whistle, hugs were shared between strangers and wefies with the Japanese fans were sought.

Argentinian, English and even Spanish fans were spotted invading the area the Ultra Nippon had occupied, eager to soak in the atmosphere the Japanese fans created, and even tried joining in the chants themselves on what was one of the most astonishing nights in the World Cup’s 92-year history.

For a precious few minutes, Costa Rica had even led Germany and it appeared as though they and Japan would progress at the expense of the two former champions. But Germany scored three goals in the final 17 minutes to win 4-2, a result which helped Spain advance.

The euphoria of the Japanese was in stark contrast to the mood in Germany. There, in a quickly-emptying east Berlin bar, Eric Warncke, 27, was “disappointed” but said he already suspected it might happen.

“Nobody expected Japan to beat Spain, but in the end we were knocked out deservedly,” he added. To his mind, there are “too few characters, too few leaders” in Hansi Flick’s squad compared with the previous sides.

“Individually they are all good players, but it’s not a team,” Warncke noted, lamenting the disappearance of Bastian Schweinsteiger and Lukas Podolski, who lifted the trophy in 2014.

Germany should have made it “to the quarter-finals, definitely”, said Levent Lanzke, 41.

“On paper it was possible, but Japan turned up. Costa Rica, too,” he added with a shrug. “Put it this way, I don’t begrudge Japan.”

Japan will now face 2018’s beaten finalists Croatia in the round of 16 on Monday, looking to reach the quarter-finals for the first time. Spain take on Morocco on Tuesday.

“Whatever happens from now,” said 28-year-old Hiroki Yamashita, “I believe this is already our best World Cup.”

For now, the Japanese flag will continue to fly proudly in Qatar.

• Additional reporting from AFP