Werder Bremen striker Yuya Osako scored twice in 11 second-half minutes to help four-times champions Japan into the final of the Asian Cup with a 3-0 victory over tournament favourites Iran on Monday.
Osako headed the first home in the 56th minute and added his second from the penalty spot to help set up a date with either hosts the United Arab Emirates or Qatar in Friday's final in Abu Dhabi.
Genki Haraguchi put a gloss to the scoreline with a powerful run and shot in stoppage time at the end of the match, but the contest was already long decided.
Iran had been the form team of the tournament but their dreams of a ending a 43-year wait for a fourth continental title were left in tatters by the clinical Samurai Blue.
Carlos Queiroz announced in the postmatch news conference that his nearly eight-year run as Iran coach, which took in two World Cups, was over.
"I think the simplest thing to do is to copy the old song: 'and now, the end is here,'" the Portuguese said, misquoting the song Frank Sinatra made famous. "I'm happy and proud to say I did it my way."
Roared on by a noisy majority of the crowd, the Iranians had enjoyed the better of a competitive, if goalless, first half but were completely deflated by Osako's twin strikes and never looked like fighting their way back into the match.
"We knew it was going to be tough but the players showed great fighting spirit," said Japan coach Hajime Moriyasu. "I'm happy the players showed that fighting spirit and really went for the win."
While Iran might have had a case that Morteza Pouraliganji's arm blocked Takumi Minamino's cross accidentally for the penalty, the opening goal was down to the sort of lapse of concentration that Queiroz has warned his team against.
Minamino had made a break down the left and crumpled to the floor on the edge of the area looking for a free kick or penalty.
None was forthcoming but while defender Ehsan Hajsafi was asking the referee to book the striker for a dive, Minamino raced to retrieve the ball and crossed it from the corner flag for Osako to head home unchallenged.
"It was very competitive, quite balanced game, until one error by my team, a naive error. We were all expecting action from the referee over the simulation," said Queiroz.
"It was an emotional breakdown from my players and after that there was only one team on the pitch."
It was the first goal Iran had conceded in six games at the tournament, but winger Alireza Jahanbakhsh came close to equalising five minutes later with a free kick that forced a good save out of Shuichi Gonda.
The second blow landed soon afterwards when the referee pointed to the spot after the ball had struck Pouraliganji on the arm, confirming his decision following a look at the TV pictures on the sideline.
Osako sent goalkeeper Alireza Beiranvand the wrong way from the spot and a fifth final in the last eight versions of the continental championship looked assured, Haraguchi helping to wrap up their first win by a margin of more than one goal at the tournament.