The two teams had met in the semifinals of the previous edition, with Japan emerging 3-0 winners and it looked on course to repeat the win when it took the lead before the half-hour mark, but two second-half goals from Mohammad Mohebi and Jahanbakhsh turned things around for the Iranians at the Education City Stadium in Doha, Qatar.
Hidemasa Morita embarked on a solo run in the 28th minute to beat three Iranian defenders and arrive into the box before drilling an effort that made its way into the back of the net despite goalkeeper Alireza Beiranvand’s best efforts to make the save.
Iran’s biggest chance to equalize before the break was a Saman Ghoddos half-volley after he controlled the ball with his chest, but the Brentford midfielder narrowly missed the target.
Nine minutes after the restart, Team Melli was able to restore parity after a long pass from Suzuki was interrupted and the ball fell to Sardar Azmoun who supplied a through pass to Mohebi. The forward was left with just the goalkeeper to beat and coolly slotted into the bottom corner for the equalizer.
Deep into four minutes of added time, Iran got a golden chance to win the game when Ko Itakura brought Hussein Kanaani down inside the box.
Jahanbakhsh stepped up and emphatically dispatched it into the top corner to earn coach Amir Ghalenoei’s side the all-important victory.
Iran will meet the winner of the Qatar and Uzbekistan match on Tuesday.