Well, what a match that was. The World Cup has delivered once again.
But the action does not stop - head over here where my colleague Michael Emons will guide you through today's second game in Group E as Spain take on Costa Rica.
Japan have a better-than-72% chance of reaching the round of 16 now, according to Opta.
They rank Germany's hopes as less than 37%. Holland are top, on almost 98%, closely followed by England and France - but you'd back a mockery to be made of those figures, if these upsets keep coming.
'Questionable decision to take Musialia off'
FT: Germany 1-2 Japan
Archie Rhind-Tutt
Football journalist on BBC Radio 5 live
Taking off Jamal Musiala given the form he's in. He started the game a bit shakily but after that, he was Germany's most dangerous player. Perhaps he was blowing but from where I was looking, I still think that's a questionable decision.
I understand why Hansi Flick put on Niclas Fullkrug and taking off Thomas Muller as well because he hasn't played a full game since the end of September so I can see the thinking, it's just did he choose the right pieces at the right time?
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SMS Message: Japan have been superb in that second half. Fantastic for them but yet again another disappointing World Cup start for Germany. from Tom
Japan have been superb in that second half. Fantastic for them but yet again another disappointing World Cup start for Germany.
'German have got work on their hands to get out of the group'
FT: Germany 1-2 Japan
Chris Sutton
Former England striker on BBC Radio 5 Live
This group now is wide open. Hansi Flick and his German team are under real pressure. They had so much control and you couldn't see them losing this game after 60 minutes but they did.
They've got real work on this hands now to get out of this group. Japan are in a wonderful position.
What a strange World Cup we have had so far, it's great.
Records go tumbling
FT: Germany 1-2 Japan
OptaCopyright: Opta
Japan used 26% of possession to hand Germany their first defeat in 26 games after scoring the opening goal in the World Cup.
Last time this happened, Lothar Matthaus put Germany ahead and Hristo Stoichkov and Yordan Letchkov gave Bulgaria victory and a semi-finals berth in July 1994.
Germany have lost after leading at half-time in the World Cup for the first time since June 1978, against Austria. They'd gone 21 games without defeat after leading at the interval at the finals.
Watch: Germany cover mouths in armband row
FT: Germany 1-2 Japan
Before kick-off the Germany players covered their mouths during the team photograph amid the row with Fifa over the OneLove armband.
The gesture follows Fifa threatening players with a booking for wearing the OneLove armband during games in Qatar.
The captains of seven European nations were set to wear it to promote diversity and inclusion.
#bbcfootball or text 81111 (UK only - standard message rates apply)
Ian: If Spain and Japan both beat Costa Rica, then Germany have to beat Spain or they’re out…
Watch: Doan cancels out Gundogan's opener
FT: Germany 1-2 Japan
It feels like a long time ago when Ilkay Gundogan put Germany ahead from the penalty spot in the first half before Ritsu Doan deservedly levelled for Japan after the break.
'Japan have made their mark'
FT: Germany 1-2 Japan
Chris Sutton
Former England striker on BBC Radio 5 Live
What a strange World Cup! What a strange game. Japan weren't in it in the first half. Germany were controlling it. Then all of a sudden, Japan show they can play. Then Asano with a brilliant finish, he lifts the ball into the roof of the net past Neuer. The Germans got desperate, Hansi Flick's substitutions were woeful and they went direct.
Japan held out and this group is really interesting. Spain, Germany, Costa Rica and Japan. Japan have made their mark now and the Germans have work to do.
Watch: Asano scores winner for Japan
FT: Japan 1-2 Germany
Here is that winning goal from Takuma Asano.
You can question the Germany defence, but it was a great first touch and finish from the Japan substitute.
Post update
FT: Germany 1-2 Japan
Shamoon Hafez
BBC Sport at Khalifa International Stadium
What a noise at the end there when the referee blew the final whistle.
The Japan subs came piling onto the pitch and they all wanted a piece of winning goalscorer Takuma Asano.
Germany threw everything at them in the end, Manuel Neuer even came close to heading in, but they've quietly trudged off down the tunnel.
Post update
FT: Germany 1-2 Japan
Credit to Japan coach Hajime Moriyasu, as well. His changes at half-time and during the second half turned the game around.
All the Japan players are gathering into a huddle on the pitch, with Moriyasu delivering what looks like a rousing speech.
Tak-ing his chance
FT: Germany 1-2 Japan
Getty ImagesCopyright: Getty Images
Even though he was a 56th-minute substitute, Takuma Asano found the ball at his feet in the opposition box more than any Germany players except Jamal Musiala and Serge Gnabry.
He made one of those five touches count to sensational effect. What a shock that goal has provided!
Post update
FT: Germany 1-2 Japan
All the Japan substitutes run on the pitch to celebrate with their team-mates. The Japan fans bedecked in blue in the crowd are going wild.
What a moment for them. What a moment for the tournament.
Get Involved
#bbcfootball or text 81111 (UK only - standard message rates apply)
SMS Message: Japan have impressed everyone with those goals. Germany don't know what hit them. from Anon
Japan have impressed everyone with those goals. Germany don't know what hit them.
FULL-TIME - Germany 1-2 Japan
JAPAN HAVE DONE IT!!
It is another shock at this World Cup as Japan come from behind to beat four-time world champions for the first time in their history!
Getty ImagesCopyright: Getty Images
Post update
Germany 1-2 Japan
Japan clear the corner. A brilliant defensive header.
Seconds left now...
Post update
Germany 1-2 Japan
Great defending!
A Japan head just diverts the ball away from Manuel Neuer - yes Manuel Neuer - before Niklas Sule's effort for a corner.
Post update
Germany 1-2 Japan
Germany have a free-kick over on the right touchline.
Live Reporting
Tom Mallows
All times stated are UK
Getty ImagesCopyright: Getty Images 
OptaCopyright: Opta 
Getty ImagesCopyright: Getty Images 
Getty ImagesCopyright: Getty Images
Latest PostPost update
Well, what a match that was. The World Cup has delivered once again.
But the action does not stop - head over here where my colleague Michael Emons will guide you through today's second game in Group E as Spain take on Costa Rica.
You can also read Emma Sanders' match report from Japan's historic win over Germany here and watch highlights in the video below.
Knockouts-bound?
FT: Germany 1-2 Japan
Japan have a better-than-72% chance of reaching the round of 16 now, according to Opta.
They rank Germany's hopes as less than 37%. Holland are top, on almost 98%, closely followed by England and France - but you'd back a mockery to be made of those figures, if these upsets keep coming.
'Questionable decision to take Musialia off'
FT: Germany 1-2 Japan
Archie Rhind-Tutt
Football journalist on BBC Radio 5 live
Taking off Jamal Musiala given the form he's in. He started the game a bit shakily but after that, he was Germany's most dangerous player. Perhaps he was blowing but from where I was looking, I still think that's a questionable decision.
I understand why Hansi Flick put on Niclas Fullkrug and taking off Thomas Muller as well because he hasn't played a full game since the end of September so I can see the thinking, it's just did he choose the right pieces at the right time?
Get Involved
#bbcfootball or text 81111 (UK only - standard message rates apply)
'German have got work on their hands to get out of the group'
FT: Germany 1-2 Japan
Chris Sutton
Former England striker on BBC Radio 5 Live
This group now is wide open. Hansi Flick and his German team are under real pressure. They had so much control and you couldn't see them losing this game after 60 minutes but they did.
They've got real work on this hands now to get out of this group. Japan are in a wonderful position.
What a strange World Cup we have had so far, it's great.
Records go tumbling
FT: Germany 1-2 Japan
Japan used 26% of possession to hand Germany their first defeat in 26 games after scoring the opening goal in the World Cup.
Last time this happened, Lothar Matthaus put Germany ahead and Hristo Stoichkov and Yordan Letchkov gave Bulgaria victory and a semi-finals berth in July 1994.
Germany have lost after leading at half-time in the World Cup for the first time since June 1978, against Austria. They'd gone 21 games without defeat after leading at the interval at the finals.
Watch: Germany cover mouths in armband row
FT: Germany 1-2 Japan
Before kick-off the Germany players covered their mouths during the team photograph amid the row with Fifa over the OneLove armband.
The gesture follows Fifa threatening players with a booking for wearing the OneLove armband during games in Qatar.
The captains of seven European nations were set to wear it to promote diversity and inclusion.
For more on this story head over here.
Get Involved
#bbcfootball or text 81111 (UK only - standard message rates apply)
Ian: If Spain and Japan both beat Costa Rica, then Germany have to beat Spain or they’re out…
Watch: Doan cancels out Gundogan's opener
FT: Germany 1-2 Japan
It feels like a long time ago when Ilkay Gundogan put Germany ahead from the penalty spot in the first half before Ritsu Doan deservedly levelled for Japan after the break.
'Japan have made their mark'
FT: Germany 1-2 Japan
Chris Sutton
Former England striker on BBC Radio 5 Live
What a strange World Cup! What a strange game. Japan weren't in it in the first half. Germany were controlling it. Then all of a sudden, Japan show they can play. Then Asano with a brilliant finish, he lifts the ball into the roof of the net past Neuer. The Germans got desperate, Hansi Flick's substitutions were woeful and they went direct.
Japan held out and this group is really interesting. Spain, Germany, Costa Rica and Japan. Japan have made their mark now and the Germans have work to do.
Watch: Asano scores winner for Japan
FT: Japan 1-2 Germany
Here is that winning goal from Takuma Asano.
You can question the Germany defence, but it was a great first touch and finish from the Japan substitute.
Post update
FT: Germany 1-2 Japan
Shamoon Hafez
BBC Sport at Khalifa International Stadium
What a noise at the end there when the referee blew the final whistle.
The Japan subs came piling onto the pitch and they all wanted a piece of winning goalscorer Takuma Asano.
Germany threw everything at them in the end, Manuel Neuer even came close to heading in, but they've quietly trudged off down the tunnel.
Post update
FT: Germany 1-2 Japan
Credit to Japan coach Hajime Moriyasu, as well. His changes at half-time and during the second half turned the game around.
All the Japan players are gathering into a huddle on the pitch, with Moriyasu delivering what looks like a rousing speech.
Tak-ing his chance
FT: Germany 1-2 Japan
Even though he was a 56th-minute substitute, Takuma Asano found the ball at his feet in the opposition box more than any Germany players except Jamal Musiala and Serge Gnabry.
He made one of those five touches count to sensational effect. What a shock that goal has provided!
Post update
FT: Germany 1-2 Japan
All the Japan substitutes run on the pitch to celebrate with their team-mates. The Japan fans bedecked in blue in the crowd are going wild.
What a moment for them. What a moment for the tournament.
Get Involved
#bbcfootball or text 81111 (UK only - standard message rates apply)
FULL-TIME - Germany 1-2 Japan
JAPAN HAVE DONE IT!!
It is another shock at this World Cup as Japan come from behind to beat four-time world champions for the first time in their history!
Post update
Germany 1-2 Japan
Japan clear the corner. A brilliant defensive header.
Seconds left now...
Post update
Germany 1-2 Japan
Great defending!
A Japan head just diverts the ball away from Manuel Neuer - yes Manuel Neuer - before Niklas Sule's effort for a corner.
Post update
Germany 1-2 Japan
Germany have a free-kick over on the right touchline.
Manuel Neuer has gone up for it.
Into the final minute of stoppage time....