Hosts Japan stunned Ireland 19-12 in an extraordinary upset that put themselves in pole position to reach the knockout stages of Rugby World Cup for the first time
The 'Brave Blossoms' came from behind at Shizuoka Stadium, with Kenki Fukuoka's second-half try and Yu Tamura's boot beating a side recently ranked No.1 in the world in a shock to match their victory over two-time world champions South Africa four years ago.
While they stunned world rugby then, winning this time in front of an uproarious home crowd, with so much focus on Asia's first World Cup, was arguably more significant.
The hosts were utterly worthy winners and after admitting their nerves got the better of them in the 30-10 curtainraising win over Russia, there was no repeat eight days later.
They came flying out of the blocks and after Kotaro Matsushima was a bounce away from getting his fourth try of the World Cup, Tamura missed an easy penalty chance to turn 10 minutes of impressive phases into three points.
He would barely put a foot wrong after that.
Once Ireland got a foothold, their gameplan became obvious - attacking off the kind of forward pressure that smashed the Scots and testing the Japanese with the clever array of kicking from five-eighth Jack Carty.
The 27-year-old late bloomer, who started his first test last month and was not part of the Ireland set up until this year's Six Nations, found the dangerous Garry Ringrose with a pinpoint crossfield kick for the first try on 14 minutes and a dink over the top seven minutes later put Rob Kearney in.
Tamura knocked over a penalty in between the two tries and Japan showed the first signs that they were not going away.
They had Ireland on the ropes for the remainder of the half, leading to two more Tamura penalties and an exhausted-looking Irish defence happy to hear the halftime whistle 12-9 ahead.
Japan, who had never finished within 16 points in seven previous defeats to Ireland, were back at it after the break with more high-tempo attacking play and Ireland already looked like they were hanging on, as their penalty count inched up.
Shell-shocked, Joe Schmidt's men made uncharacteristic simple errors and Fukuoka, a last-minute addition to the bench, after an injury to Will Tupou, sensationally gave Japan the lead with 20 minutes to go and Tamura slotted over his most difficult kick of the night to make it 16-12.
Ireland, who chose not to risk first choice five-eighth Jonny Sexton, after he did not train fully this week, simply had no answer, and with the home fans getting louder and louder, Tamura extended the lead to seven points eight minutes from time.
Japan finished the game deep in the Irish half to top Pool A with two wins from two and open up a group Ireland were heavy favourites to top.
Japan 19 (Kenki Fukuoka try; Yu Tamura conversion & four penalties) Ireland12 (Rob Kearney, Garry Ringrose tries; Jack Carty conversion).
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