Mascherano is happy to be playing on the same side as his compatriot.
"Messi is the best player in the world," he said.
"We have the good fortune to have him on our side and let's hope we can all help him.
"That doesn't mean that, because he is the best player in the world, that he is going to decide the game on his own, but it's an advantage. And I prefer to have him on my side."
On the whole, Mascherano believes his first season in Spain has been a success, but says Saturday's result could change that - for better or for worse.
"One usually makes an analysis once the season is over and the season still isn't over for us," he said.
"Obviously I'm very happy with how things have gone but one result can change the way you view a season and especially a result like the one on Saturday.
"Obviously I'm happy, but like any human being, I want more."