Japan responded to their opening defeat to Samoa by edging Tonga 28-27 in the Pacific Nations Cup.
Japan crossed for three tries in 17 minutes either side of the break to seal a come-from-behind win.
Kurt Morath had put Tonga 17-7 up before the half-hour after recording a converted try, a penalty and two points from Viliame Ma'afu's effort.
But then Japan got into their stride thanks to tries from wing Kosuke Endo, Takashi Kikutani and Koji Taira going over and James Arlidge kicking the conversions, opening up an eleven-point lead.
Tonga then launched a comeback charge of their own but despite a try from replacement Hudson Tongauiha, they fell short of the mark.
Tries: Holani, Endo, Kikutani, Taira
Con: Arlidge 4
Tries: Ma'afu, Morath, Tongauiha
Con: Morath 3
Pen: Morath 2
Japan: 15 Sean Webb, 14 Kosuke Endo, 13 Koji Taira, 12 Ryan Nicholas, 11 Hirotoki Onozaw, 10 James Arlidge, 9 Fumiaki Tanaka, 8 Koliniasi Ryu Holani, 7 Michael Leitch, 6 Takashi Kikutani (c), 5 Luke Thompson, 4 Justin Ives, 3 Kensuke Hatakeyama, 2 Yusuke Aoki, 1 Hisateru Hirashima.
Replacements: 16 Shota Horie, 17 Naoki Kawamata, 18 Histoshi Ono, 19 Itaru Taniguchi, 20 Atsushi Hiwasa, 21 Go Aruga, 22 Takehisa Usuzuki.
Tonga: 15 Vungakoto Lilo, 14 Viliami Helu, 13 Alaska Taufa, 12 Andrew Mailei, 11 Viliame Longi, 10 Kurt Morath, 9 Samisoni Fisilau, 8 Sione Kalamafoni, 7 Viliami Ma'afu (c), 6 Lisiate Faaoso, 5 Joe Tuneau, 4 Paino Hehea, 3 Semisi Telefoni, 2 Ifalemi Taukafa, 1 Alisona Taumalolo.
Replacements: 16 Ilaisa Ma'asi, 17 Maleko Latu, 18 Tukulua Lokotui, 19 Sione Vaiomounga, 20 Soane Havea, 21 Hudson Tonga'uiha, 22 Mateo Malupo.