River Plate coach Marcelo Gallardo wants his players to show passion and belief in order to spring a shock against Barcelona in Sunday's Club World Cup final.
Spanish and European champions Barca are favourites to add the world crown to their list of titles collected during a phenomenal 2015.
"We made a great effort to be here – it has been a long journey and we have given everything," Gallardo told a pre-match news conference in Yokohama.
"This game is not only important in the history of River but in the history of Argentine football.
"It's a great challenge for us. Barca are the best in the world right now.
"They have the best players but we have a big heart. It is a duel of the highest level.
"We will enjoy the game because it is an opportunity that occurs once in a lifetime."
Barcelona cruised to a 3-0 semi-final victory over Guangzhou Evergrande Taobao thanks to a Luis Suarez hat-trick.
The club's other star forwards, Lionel Messi and Neymar, were absent through illness and injury respectively.
Neymar is expected to make his return in the final and Gallardo feels it would be a shame for either player to miss out on what promises to be a memorable occasion.
"I would like to play [against] those two," he added. "For me it is a pleasure to deal with two of the three best players today."