The 33-year-old helped Argentina book their place in Russia when they came from behind to beat Ecuador 3-1 thanks to Lionel Messi's superb hat-trick.
Before ending his international career, Mascherano wants to help his club and country team-mate taste international success.
"For a lot of people the story could have finished, but thanks to God it was not like this," Mascherano told Spanish newspaper Sport.
"If I get to Russia, that will be the end. I know that for sure.
"Lionel Messi owns this game and when you own the game you have ability to make things happen.
"I hope we can help him in Russia. We enjoyed him and now we have to help him. We have the chance to dream.
"It's a World Cup and we can remember how we played in Brazil (when they reached the final in 2014).
"We have to prepare in these seven or eight months to arrive in the best form possible, and we'll try to do it."