River Plate advanced to the Club World Cup final with a 1-0 victory over Sanfrecce Hiroshima in Japan on Wednesday.
Lucas Alario secured the Argentinians' spot in Sunday's final, heading in the only goal in the 72nd minute.
The forward pounced to nod a loose ball into the net after Sanfrecce goalkeeper Takuto Hayashi had made a mess of trying to claim it from a free-kick.
Marcelo Gallardo's team will face the winner of Thursday's semi-final clash between Barcelona and Chinese outfit Guangzhou Evergrande.
Wednesday's other match saw Mexico's Club America claim fifth place in the tournament with a 2-1 win over Congolese side TP Mazembe.
Dario Benedetto put the Mexicans in front with a header in the 19th minute and after he was then substituted with injury, his replacement, Martin Zuniga, struck to make it 2-0 in the 28th before Rainford Kalaba's 43rd-minute reply.
