Before the New York Yankees, before the All-Star appearances and World Series rings, Jorge Posada was a teenager with one goal.

"I wanted to be a big league baseball player no matter what," the former catcher tells CNBC Make It. "I didn't have a Plan B. Plan A was that I was going to be a big league player." 

While his career in New York was filled with plenty of success — Posada won four straight Silver Slugger Awards from 2000-2003 — it wasn't pure talent that got him to the top. 

"I wasn't the best player on my little league team," he says. "I wasn't the best player at my college. I wasn't the best player in the minor leagues. But I knew I wanted it more than anybody else, and I worked harder than anybody else to get there." 

Posada spoke with CNBC Make It while promoting his appearance in Miller Lite's Great Taste, Less Filling campaign. Below, he talks about the advice that helped him get to the big leagues, learning from a Yankee legend and how he dealt with pressure. 

The best advice Jorge Posada ever received

Though he's shared locker rooms with multiple Hall of Fame players, Posada says the best career advice he ever received came from his father. 

"My dad always said, 'Don't lose your job because somebody is working harder than you,'" he tells Make It. "That, for me, helped me so much throughout my career." 

His dad's advice helped Posada stay disciplined in his training as he worked toward his dream of making it to the major leagues. 

"Wanting it so badly made me realize that I needed to work harder than most people. I needed to be more disciplined and stay away from things that would keep me away from the game," he says. "It helped me stay away from bars and stay away from kids who weren't focused."

Learning by example

Posada learned early on that "somebody was always watching" how he carried himself on the field and in practice, whether it was a member of the Yankees' brass, a scout for another team or a kid in the stands. 

Indeed, he became a better player himself by observing how a Yankees legend carried himself when nobody else was looking. 

"My first Spring Training I was with Don Mattingly down in Fort Lauderdale. I would get to the field pretty early and he was already there hitting or taking fly balls or ground balls in the back field," Posada says. 

The next day, the then-minor-leaguer showed up even earlier in an attempt to get there at the same time as the team's captain. 

"He was there, already sweating. The sun wasn't even out," Posada says. "I could never beat him. He taught me so much. I saw the best player doing all this hard work and putting in all this time and I was like, 'I don't think I'm doing enough.'"

The mindset that someone is always watching had another side effect beyond helping Posada continue to improve. 

"It's a lot of fun when you give it your all and you get home and feel pleased with what you tried to accomplish on the field," he says.

The benefits of a positive mindset

When it comes to dealing with pressure-filled situations, Posada says the best approach begins with a positive mindset. 

"Being unprepared is probably the worst thing that can go through your mind," he says. 

For Posada, approaching an at-bat with the game on the line involved putting the thought of failure out of his mind altogether. 

"Practice makes perfect. [Remember] you put yourself in a situation to succeed," he says. "Try to think of everything positive, you don't think about the failure part. Tell yourself, 'I've been here before. I've done this. I'm prepared."

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