Japan made up for last weekend's disappointment when they claimed a historic 23-8 victory over Wales in Tokyo on Saturday.
The hosts' win - their first ever triumph over Wales - is sweet revenge after they suffered a narrow 22-18 loss to their opponents in Osaka last Saturday and secures them a 1-1 draw in the series.
Japan full-back Ayumu Goromaru opened the scoring from the kicking tee in the 15th minute after Rhys Gill was penalised for infringing at a ruck.
The visitors struck back with a penalty of their own from Dan Biggar in the 22nd minute and were slowly gaining the upper-hand but could not convert their dominance into points.
In the 26th minute Rhys Patchell came close to scoring the game's opening try after gathering an inside pass from Biggar which saw him slipping past a couple of defenders but he was stopped short of the line by a desperate tackle from Japan's captain Toshiaki Hirose.
Japan held a 6-3 lead at half-time after Goromaru landed a penalty from just inside his half after Lloyd Williams infringed at a ruck.
Wales started the second half brightly and were rewarded with a try in the 45th minute when Tom Prydie scored in the left-hand corner after gathering a long pass from Biggar inside Japan's 22.
Wales' resurgence was a brief one as the hosts struck back with a well-taken try from their inside centre Craig Wing shortly afterwards. Confronted with a couple of tight forwards close to Wales' try-line Wing burst through a tackle from Gill before squeezing over for his side's first try.
Goromaru added the extras to give the home side a 13-8 lead and 10 minutes later the Brave Blossoms were rewarded with their second try after a period of sustained pressure deep inside the visitors' half.
After taking the ball through several phases inside Wales' 22 with their forwards, scrum-half Fumiaki Tanaka, who proved a handful for Wales throughout, whipped out a long pass to Hirose who offloaded to openside flanker Michael Broadhurst who got in for an easy five-pointer.
Goromaru added the conversion to maintain his perfect goal-kicking record and although Wales tried gallantly to fight back for the rest of the game, the home side were well prepared and kept them at bay with resilient defence.
Five minutes before the final whistle, Goromaru added the final nail to Wales' coffin, when he added another penalty to seal a memorable victory for the home side.
Tries: Wing, Broadhurst
Japan: 15 Ayumu Goromaru, 14 Toshiaki Hirose (capt), 13 Male Sau, 12 Craig Wing, 11 Kenki Fukuoka, 10 Harumichi Tatekawa, 9 Fumiaki Tanaka, 8 Takashi Kikutani, 7 Michael Broadhurst, 6 Hendrik Tui, 5 Shoji Ito, 4 Hitoshi Ono, 3 Hiroshi Yamashita, 2 Shota Horie, 1 Masataka Mikami.
Replacements: 16 Takeshi Kizu, 17 Yusuke Nagae, 18 Kensuke Hatakeyama, 19 Shinya Makabe, 20 Justin Ives, 21 Atsushi Hiwasa, 22 Yu Tamura, 23 Yoshikazu Fujita.
Wales: 15 Liam Williams, 14 Harry Robinson, 13 Owen Williams, 12 Jonathan Spratt, 11 Tom Prydie, 10 Dan Biggar, 9 Lloyd Williams, 8 Andries Pretorius, 7 Josh Navidi, 6 James King, 5 Lou Reed, 4 Bradley Davies (c), 3 Scott Andrews, 2 Emyr Phillips, 1 Rhys Gill.
Replacements: 16 Scott Baldwin, 17 Rhodri Jones, 18 Craig Mitchell, 19 Andrew Coombs, 20 Dan Baker, 21 Tavis Knoyle, 22 Rhys Patchell, 23 Dafydd Howells.
Referee: Greg Garner (England)