The hosts grabbed a last-gasp bonus point in their 38-19 win to move top of Pool A on 14 points, with second-placed Ireland on 11 and Scotland, who play their game in hand against Russia in Shizuoka on Wednesday on five.
It means the Scots must look to beat the Russians with a bonus point then defeat Japan while denying them any in Yokohama next Sunday in what is shaping up as a momentous finale to the pool stage in front of a crowd of 70,000.
Essentially, Scotland must take at least four more points than Japan from a win. If they fail to take a bonus point against Russia that rises to five. In the unlikely but not impossible scenario that Scotland, Japan and Ireland all finish on 15 points it would come down to points difference.
“It has made the picture clearer for us, what we need to do against Russia first and what we need to do against Japan in the last game. The picture is very clear now,” was Fagerson’s positive take on the situation.
There has been much anger from Scottish fans on social media about the way the last few, potentially pivotal seconds played out in Toyota.
Japan had only just got themselves to three tries minutes before when, with the clock past 80 minutes, Samoa were awarded a free kick. At 31-19 down, they could have kicked out to end the game but instead opted to scrum against a rampant Japanese pack. They were then picked up by South African referee Jaco Peyper for a squint put in - something which has hardly, if ever, been penalised in the tournament so far.
Japan turned the screw and got the try they needed through Kotaro Matsushima.
“Samoa were in the game, they scored that try and from the restart Japan got the ball back,” said Fagerson, who was watching the dramatic denouement with the rest of the Scotland squad.
“It was an exciting game to watch, there was some great rugby on show from both teams. Japan are a very fit team and showed that in the last little bit, the fitness proved enough to win the game.”
Even if Japan had failed to take that bonus Scotland still need to win both their remaining games, though now with even less wiggle room and an understanding that the next 160 minutes need to be squeezed for every last drop while giving nothing to the hosts in Yokohama.
“We have Russia first and if we don't get the job done against Russia there is no point in even thinking about Japan because we need those five points.
“Everything is focused on Russia now and getting that bonus-point win.”
Glasgow tighthead Fagerson said he is ready to play a part in both matches, which will be played with just four days break inbetween.
“If the opportunity arises will grasp it with both hands. To be at a World Cup is a great achievement but you are only halfway there, I want to play as much as I can. If the opportunity arises I’d love to play [in both].”
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