Making millions as a teen 'was a culture shock'—here's the money advice Alex Rodriguez would give his younger self

Retired baseball star Alex Rodriguez became a millionaire quickly and at a young age: He went straight from high school to the big leagues and signed a three-year, $1.3 million contract with the Seattle Mariners after being drafted in 1993. He also got a $1 million signing bonus.

And that was just the beginning of his lucrative career: He went on to sign a 10-year, $252 million contract with the Texas Rangers in 2000, which was the largest in MLB history at the time.

Earning so much at a young age "was a culture shock for me and those around me," Rodriguez tells The New York Times Magazine in a recent interview.

Rodriguez and his two siblings were raised by a single mother, Lourdes Navarro, who worked at the 24-hour chicken restaurant Pollo Supremo to make ends meet. The family had to move every 18 months, whenever the landlord raised the rent.

"You have a young kid who learned how to play baseball at the Boys & Girls Clubs," A-Rod tells The NYT Magazine. "Then you climb through the system, you become the No. 1 draft pick. You bypass college. At 21, you get over $10 million in a contract, which is crazy."

"Usually journeys have an arc of many years," he adds, "but this all happened to me in seven or eight years after high school. … There's no preparation for it."

If Rodriguez could give his younger self one piece of money advice, it's the same thing he would tell any athlete today: Plan ahead by making smart investments now.

"You're going to make probably 90% to 95% of your lifetime income from age 20 to 30, and you have to ask yourself, 'What's going to happen from age 30 to 80?'" he tells CNBC Make It.

While an athlete's career can be incredibly lucrative, as Rodriguez notes, it can also be short-lived. On average, an MLB player can expect to last 5.6 years in the league. The average career length for other professional athletes is even shorter: less than five years for NBA players and just 3.3 years for NFL players.

Still, "you have an incredible opportunity if you're frugal and you're smart and you put your money away early," says Rodriguez. "The ability to have compound interest over 20, 30, 40 years — you can be a very wealthy young person in a very short period of time. "

Rodriguez, who played his last game as a New York Yankee in August 2016, is now a baseball broadcaster and CEO of investment firm A-ROD CORP.

He's also built relationships with legendary investor Warren Buffett and other C-suite leaders, and he has taken business classes at the University of Miami, Columbia University and Stanford.

Ultimately, learning is the key to long-term success, Rodriguez tells CNBC: "Knowledge is power. … If you stop learning, you stop living."

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