Japan head coach Jamie Joseph is looking forward to "a real ripper" of a game when his team plays Scotland in its final Rugby World Cup pool match next Sunday.
But the Brave Blossoms' rampant form means they may have already wrapped up a first-ever place in the quarterfinals by then.
Japan beat Samoa 38-19 at City of Toyota Stadium on Saturday night to make it three wins out of three at the tournament, picking up a bonus point with the last play of the game to move within touching distance of the knockout phase.
The Brave Blossoms' record so far means they may be able to progress to the last eight even if they lose against Scotland in Yokohama, but with the Scots first needing to beat Russia in Shizuoka on Wednesday to stand any chance of qualification, the matter could already be decided before Sunday's showdown.
"Scotland have another game to play, then it will all pan out," said Joseph. "It's obviously better having a bonus point and it was difficult to get it, and it may be the difference in the very end.
"I think it was always going to come down for us, if we were playing to our potential, to the final game against Scotland. So it's revving up to be a real ripper. I can't wait. I know the players can't wait because we've been subconsciously thinking about it for a couple of years now. So we'll just wait and see how they get on against Russia."
Japan, coming off the back of the previous week's momentous 19-12 win over Ireland, started nervously against Samoa but led at halftime thanks to a Timothy Lafaele try.
Kazuki Himeno scored another in the second half before substitute Kenki Fukuoka grabbed a late third to nip a Samoan revival in the bud, but it was Japan's last-gasp fourth try that could really end up making the difference.
Japan was awarded a free kick from a Samoan scrum near the opposition goal line, and chose to scrum down again in the hope of pushing the Pacific Islanders back further. Japan won the ball and worked it out left to winger Kotaro Matsushima, who shimmied over the line to secure what could be a crucial bonus point for his team.
"The forwards put a lot of pressure on them with the scrum, and the backs put them under pressure as well," said Matsushima, who scored his fourth try of the tournament following a hat trick in the tournament opener against Russia. "I knew that if there was a chance, Fumiaki Tanaka would pass it out to me. That's what actually happened, and I'm glad I was able to get the ball over the line and score the try.
"The team's first objective was to get the win, not the bonus point, but when the chance came along to get one, we wanted to go for it. We were able to do that and I think we're riding a good wave of momentum now."
Samoa's decision to take the initial late scrum rather than go for a free kick left many observers scratching their heads, especially as the Pacific Islanders could have earned themselves a losing bonus point if they had managed to score one more try.
"That's what I was thinking of with the last decision there," said Samoa captain Jack Lam, whose team was coming off a 34-0 loss to Scotland just five days earlier. "I thought our scrum was doing well at the time. We back our team to score from anywhere but, as you saw, our scrum didn't operate well at the end there.
"The game was well balanced. At times we did feel like we were playing against more than 15 people. We did well to turn around after getting a good hiding from Scotland. I'm proud of our boys, and all the best to Japan for the rest of the games."
Matsushima's try came in the 85th minute, and triggered wild celebrations among the 39,695-strong crowd at City of Toyota Stadium. World Cup fever is building with each victory for the home team, and second-row forward James Moore said the passion of the crowd is fueling the players' belief.
"It's unbelievable," he said. "I think Japanese rugby fans are definitely the best in the world. When you're out in the field you try to block it out and just focus on playing rugby, but sometimes it's hard with how loud it is.
"You do have a really good feeling when you go out for the game because everyone's cheering (for) you. In the warmup you're pretty pumped up. It's a great feeling."
Joseph will try to bring his players back down to earth before Sunday's game against Scotland, and having seen the Scots dispatch Samoa with ease in Kobe earlier in the week, the coach is wary of their quality.
"Scotland are a very, very good team," said Joseph. "They've got a lot of experience, a lot of X-factor, and I just saw how clinical they were in beating Samoa last week when we really struggled against that team."
