Ten-man Boca Juniors overcame Tunisia's Etoile du Sahel 1-0 to reach the final of the Club World Cup on Wednesday.
Etoile du Sahel went to Japan after winning the Champions League
Midfielder Neri Cardozo's goal in the first half secured victory for the Argentine champions in Tokyo.
Boca forward Rodrigo Palacio made a nifty move around an Etoile defender and threaded a pass to Cardozo.
Cardozo then beat goalkeeper Aymen Balbouli with a left-foot shot in the 37th minute for the lone goal of the match.
"It was not an easy match to win," Boca coach Miguel Russo said.
"But we dominated the game, made chances and took advantage of our opportunities."
Boca was reduced to 10 men in the second half when Fabian Vargas was sent off in the 65th minute after a second yellow card for a high tackle and will miss the final.
"Boca is one of the best teams in the world," Etoile coach Bertrand Marchand said.
"This was one of the best games we've ever played, we gave them a hard time but they are more experienced than us."
European champions AC Milan will face Japan's Urawa Reds in the other semi-final on Thursday in Yokohama.