Here's the money advice Alex Rodriguez would give his younger self

Here's the money advice A-Rod would give his 20-year-old self

Former MLB star Alex Rodriguez has done well for himself: Over his 22-season career as a third baseman and shortstop, he earned about $448 million.

His career began in 1994, after he was drafted first overall by the Seattle Mariners. Rodriguez, then 18, collected a $1 million signing bonus and signed a three-year, $1.3 million contract.

If Rodriguez could give his rookie-self one piece of money advice, it's the same advice he would give any athlete today, he tells CNBC Make It: "You're going to make probably 90-to-95 percent 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?'"

Alex Rodriguez was the first overall draft pick in 1993 and played for the Seattle Mariners from 1994 to 2000
Rich Pilling | Getty Images

While life as an athlete can be incredibly lucrative, as Rodriguez notes, it can also be short-lived. On average, an MLB player can expect their career to last 5.6 years. 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.

Despite the short career length, "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 Yankee in August 2016, is now transitioning to a career in business as CEO of A-ROD CORP, the holding company he started 15 years ago for his various investments.

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He's built relationships with legendary investor Warren Buffett and other C-suite leaders, and is now looking to help other professional athletes prepare for life off the field in a new CNBC show, "Back in the Game."

"If you look at the data," Rodriguez tells CNBC's "Squawk Box," "they suggest that a lot of our players are going bankrupt way too soon. … You make 90 percent of your money between age 20 to 30. Less than five percent of our guys in the major leagues have a college degree.

"What happens from age 30 to 80?"

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