South American champions River Plate booked their place in the Club World Cup final with a 1-0 win over Sanfrecce Hiroshima.
The Argentine giants were matched for large spells by the J-League champions but Lucas Alario scored in the second half with a header after Sanfrecce goalkeeper Takuto Hayashi could only half-punch a Carlos Sanchez free kick away.
Yusuke Minagawa had the best chances for Sanfrecce in the first half but failed to convert a trio of opportunities.
River face the winner of Thursday's semifinal between Barcelona and Guangzhou Evergrande on Sunday while Sanfrecce take on the loser of that game in the third-place playoff the same day.