After battling through qualifying, Jorge Sampaoli's men are not considered among the strong favourites for Russia 2018.
"We hope that we do well, that the players get well and above all Messi," the Argentinian told El Trece.
"If the latter happens, Argentina will have many chances to win. If Messi is good, nothing is complicated.
"I don't know Sampaoli. It is important that Argentina can win the World Cup. We want to celebrate and when there are players as important as Messi, you depend on them a lot."
Messi missed out on winning a sixth Ballon d'Or this year, with Cristiano Ronaldo instead joining him on a record five.
"It's Messi and we're lucky he's Argentinian. Cristiano Ronaldo served Messi and Messi Cristiano Ronaldo," he said.
"Both gave themselves strength to share the prizes. I think Messi is the best. They are incredible."