The 27-year-old joined Barcelona from Liverpool in last year and help clinch the La Liga and Champions League titles for his new club.
Mascherano has now revealed how his Argentina team-mate Messi opened the door for him to the Nou Camp.
"My relationship with Leo is spectacular. I'll be grateful for the rest of my life that he recommended me to join Barcelona," Mascherano was quoted as saying by Marca.
The defensive midfielder was utilized in the central defensive position on numerous occasion by Pep Guardiola last season.
And he insists that although it is not his natural positition, he is more than willing to play anywhere the coach deploys him.
"The coach believed in me as centre-back and I try to do the best I can. With the support of the coach, everything is easier.
"I feel proud to be part of a group that never gets tired of winning. I've never been at a team like this."
Mascherano now face further competition for a midfield place following the arrival of Cesc Fabregas from Arsenal.