Mario Martinez grew up in Monterrey, N.L., Mexico, where he first developed his love for soccer playing in the streets with neighborhood friends. His passion for the game deepened after the 1970 World Cup in Mexico, which inspired him to join organized teams. In 1976, he was invited by Ubirajara Chagas Tamega, known as "Bira"—a former professional player for F.C. Monterrey and coach of the club's youth program—to join the reserves of F.C. Monterrey. Having attended professional matches since 1968, Mario greatly admired "Bira," and meeting him in person was a pivotal moment. That experience made him realize that even after a playing career ends, one can still make a significant impact on younger generations through coaching.

In 2004, Mario’s interest in coaching began to grow as his son expressed a desire to play more competitively. That same year, he earned his U.S. Soccer "E" and "D" National Licenses and began volunteering as a head coach at the Select Level for a local club. Committed to his development as a coach, Mario went on to earn his "C" License in 2010.

Mario has been married to Claudia Martínez for 29 years, and together they have a son, Mauricio Gabriel Martínez, who is 28.