Japan lost 22-21 to Australia A on Saturday, their second straight defeat in the three-match, non-test series 11 months before the World Cup in France.
Playing as Japan XV, the hosts reclaimed the lead through former captain Michael Leitch's 62nd-minute try, but Richie Asiata scored with seconds left to make it 21-20 before Tane Edmed nailed the crucial conversion at Best Denki Stadium in Fukuoka.
"Very tough game of rugby today," Japan head coach Jamie Joseph said. "(Australia A) are used to that level of intensity...something which we have to get used to quickly."
Japan swung the visitors from one side to the other before wing Kotaro Matsushima, who came off the bench to score in their 34-22 defeat a week ago, went over down the right in the first minute.
But despite flanker Kazuki Himeno, another substitute during the first match in Tokyo, and returning fellow 2019 World Cup star Ryoto Nakamura also starting, the home team never quite managed to stamp their authority.
Slack defending in the middle of the pitch allowed fullback Jock Campbell to sprint and score in the left corner in the 31st minute as the visitors led 10-8 at the break.
Australia A stretched the lead to 15-8 in the 44th minute after fullback Tom Banks, on for the second half, raced down the left before muscling his way to score on a quick break combining with Dylan Pietsch.
With Japan failing to create many chances, Leitch, playing as No. 8 again, came to the rescue by finding a gap and grabbing a try near the center for a 16-15 lead following a lineout inside the Australia A 22.
But Japan bowed to late pressure when Asiata grounded the ball from a driving maul following a lineout deep inside the Japan 22 down the left, with Edmed scoring the extras to snatch the tourists' second win.
"It turned out to be a really frustrating game after missing out on the win right at the end," Japan captain Atsushi Sakate said.
"We made lots of adjustments from the last game, keeping possession and kicking at the right moments in attack, but we then made some mistakes or conceded penalties."
Visiting captain Ryan Lonergan said, "Japan probably had the momentum for the majority of that game," while their head coach Jason Gilmour was pleased his "boys showed lots of composure."
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