Only host Brazil is more favored to win the tournament and Messi feels his team's serious approach to warm-up matches can hold it in good stead.
Argentina plays a final friendly against Slovenia on Saturday before opening its World Cup campaign with a Group F clash against Bosnia-Herzegovina on June 15.MORE: U.S. Soccer MVP rankings | USA vs. Turkey photos
"Yes, it is just a friendly and we are very close to our trip [to Brazil] but we are going to play with all we have," said the 26-year-old. "No one wants any [injury to] occur, we are all being very careful of that, but we still all want to win, do our best, play seriously and I believe we have done that. I believe we have a very strong team, very unified and more than that we also have really great players."
Meanwhile, Messi's Barcelona and Argentina teammate Javier Mascherano echoed his thoughts and said that coach Alejandro Sabella had drummed into the squad the importance of gaining pre-tournament rhythm.
"Our minds are on the World Cup, but you have to keep playing," he said. "The team has to function well together … if not we will play poorly in our first game."