Tigres UANL midfielder Egidio Arevalo stressed the importance of his team taking their chances against River Plate.
River welcome Tigres to Buenos Aires for Wednesday's return leg, with the Copa Libertadores final all square after last week's scoreless stalemate in Leon.
Tigres were frustrated by the Argentine visitors at Estadio Universitario de Nuevo Leon, having dominated for large parts of the match.
And Arevalo knows Tigres must take advantage of their opportunities if they are to become the first Mexican team to win South America's premier club tournament.
Away goals do not count in the Libertadores final, so a score draw would not result in a Tigres triumph.
"During moments they [River Plate] were superior and controlled the match but that doesn't mean that this game will work out the same," the Uruguay international told reporters.
"So it will be different, the one who does it better, will win the game. We have to take advantage from the small goal opportunities that we'll have.
"We are calm. We know that we will fight until the last minute. The group knows what we came for and what we are facing. So let them talk, we'll see after the match.
"Us and them, we are with the same wish of gaining a title. We are facing a great opponent, it will be a hard match. I don't want to anticipate, let's see after the match if we can celebrate."
River are gunning to win the Libertadores for a third time, but they will have to do so without coach Marcelo Gallardo and full-back Gabriel Mercado.
Gallardo will watch from the stands after being sent off for yelling at the fourth official in the first leg, while Mercado is suspended, having picked up his second yellow card.
River have not won the tournament since 1996, however Gallardo is confident about his team's chances.
"We have good feelings about the game, no matter which player is on the pitch, the match will be unique and memorable, to have the chance and the willing to win," he said.
"We are taking part in one of the most valuable and prestigious tournaments We are fine.
"I think that the fans can be sure that this group of players will leave everything on the pitch. They are competitive, so when these kind of games come around, they strengthen."
