Sam, don't take this the wrong way, but this might be the nerdiest story I've ever read on ESPN.com, and yet I loved it.

Well, I mean, so much of how I learned to be a baseball fan was by studying the back of baseball cards.

When you're a kid, you're not really an expert on anything that adults care about.

But baseball is the one exception, right?

You study these cards, you memorize the numbers and the words, and you've got something

that you can contribute to in a conversation with an adult.

Arguably the most formative baseball writing in my life would have been the backs of baseball cards. I read all of

them. I learned about baseball. In subtle ways, I learned about what matters in a baseball player

and what accomplishments are worth preserving.

And so it was this incredible rush of nostalgia for me to realize that one of these cards I remembered so well still had a mystery tucked deep inside it 30 years later for me to solve.

Donne. Don Mattingly is one of the most accomplished Yankees of all time.

The nine-time gold glove winner and former MVP was so beloved he earned the nickname Donnie baseball.

But while Mattingly was a superstar, few people know that he was also

the subject of one of the strangest and dorkeiest mysteries in the history of baseball. Today,

we try to crack the case. Did Donnie Baseball himself lie about his age? And if so, why?

I'm Minicimes.

It's Wednesday, April 29th.

This is ESPN Daily.

I mean, you were sort of a detective.

Yeah, I was. I sleuthed.

Sam Miller writes about baseball for ESPN.

He is also apparently a private investigator.

...