Japan came back from a goal down to beat Germany 2-1 in a stunning World Cup Group E opener at the Khalifa International Stadium after Ritsu Doan canceled out Ilkay Guendogan's penalty and Takuma Asano netted the late winner. Here are five things we learned from the momentous win.

Moriyasu not afraid to change tack

With Japan on the ropes throughout the first 45 minutes, manager Hajime Moriyasu started the second half by changing shape from four defenders to three at the back. The tactical change proved to be a catalyst for Japan's spectacular second-half comeback.

Japan manager Hajime Moriyasu gives his players instructions during the first half of a World Cup Group E football match against Germany at Khalifa International Stadium in Doha on Nov. 23, 2022. (Kyodo)

Super subs change the game

Japan's second-half substitutions swung the game in favor of the Asian side. Goal scorers Doan and Asano were the obvious heroes, but Takehiro Tomiyasu, Kaoru Mitoma and Takumi Minamino also provided vital momentum.

Japan's Kaoru Mitoma dribbles the ball during the second half of a World Cup Group E football match against Germany at Khalifa International Stadium in Doha on Nov. 23, 2022. (Kyodo)

Squad selections vindicated

Moriyasu raised eyebrows when he named Asano in the squad while leaving out the in-form Kyogo Furuhashi, especially with the Bochum attacker yet to return from a knee injury, but Wednesday's result will silence the critics. Asano's 83rd-minute winner was a thing of beauty, with the World Cup debutant displaying speed, strength and control to corral a long ball and etch his name in history.

Takuma Asano (L) scores Japan's second goal in the second half of a World Cup Group E football match against Germany at Khalifa International Stadium in Doha on Nov. 23, 2022. (Kyodo)

The Samurai Blue's Achilles heel?

Defensive lapses on the right of the box led to two straight penalty goals by Japan's opponents. Guendogan converted Germany's 33rd-minute opener after the unmarked David Raum was brought down by keeper Shuichi Gonda near where Miki Yamane conceded a decisive late penalty in Thursday's 2-1 friendly loss to Canada.

Japan goalkeeper Shuichi Gonda (R) fouls Germany's David Raum (C) to concede a penalty during the first half of a World Cup Group E football match at Khalifa International Stadium in Doha on Nov. 23, 2022. (Kyodo)  

Gonda's assets outweigh liabilities

The Shimizu S-Pulse keeper was picked to start between the posts ahead of Sint-Truiden's Daniel Schmidt, whose strong recent performances led to a number of pundits, including former Japan players, calling for him to get the job. Gonda enabled Germany's goal, but he redeemed himself with several outstanding saves later in the match.

Japan goalkeeper Shuichi Gonda makes a save from Germany's Serge Gnabry during the second half of a World Cup Group E football match at Khalifa International Stadium in Doha on Nov. 23, 2022. (Kyodo)

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