Evan Mathis says his own football cards are so worthless, it's easy to own them all.

Mathis, a retired NFL player who spent four years of his 13-year career with the Eagles, has been a serious card collector since he was a kid, when his favorite players were Oakland Raiders running back Bo Jackson and Chicago White Sox Slugger Frank Thomas.

Mathis' extensive collection includes a 1953 Topps Mickey Mantle and every card featuring former Miami Dolphins defensive tackle Bob Baumhower, Mathis' uncle. But next month, the former offensive lineman will part ways with one of the jewels of his collection: a 1952 Mickey Mantle baseball card with a Professional Sports Authenticator (PSA) rating of 9.

Mathis is selling this 1953 Mickey Mantle rookie card, which is expected to sell at auction for as much as $3.5 million.
Heritage Auctions
Mathis is selling this 1953 Mickey Mantle rookie card, which is expected to sell at auction for as much as $3.5 million.

The card, among the most celebrated and sought-after pieces in the hobby, will be offered at Heritage Auction's spring Sports Card Auction, which will be held April 19 and 20. The card is valued at $3.5 million dollars. If it sells for that much, it would set a new record price for a baseball card, topping the $3.12 million paid for a 1909 Honus Wagner card in 2016. As of this writing, the current bid sits at $1.85 million.

"Since the last auction offering of a PSA Mint 9 example over ten years ago, the 1952 Topps Mantle rookie card has exploded in popularity and identified itself as the hobby's ultimate blue chip stock," said Chris Ivy, director of sports auctions at Heritage. "There are fewer than 10 cards equal or superior to each of these examples in the PSA population, so the gulf between supply and demand is truly massive."

Mathis talked about his love of trading cards and why he ultimately decided to part with such a valuable part of his collection. This conversation has been edited for length and clarity.

How did you get the Mantle's rookie card in the first place?

I have a lot of friends in the hobby who I exchange pictures with of stuff we have acquired or items we've come across that we think are special. A couple years ago, one of those friends sent me a picture of this particular card, as he had just acquired it. We eventually worked out a deal for it.

Why do you think it's such a prized collectable?

The 1952 Topps set is the most important post-war set for many reasons and it put the wheels in motion for what cards would become over the years. The prominence of the set has always brought attention to it. Because it's the key card in the set, the Mickey Mantle has always been the face of the hobby.

Why sell such a unique card?

My wife and I made the decision to buy a house and because so much of my investment portfolio is in cards, it made sense to liquidate some instead of getting a mortgage or selling off our traditional investments. This one card will completely pay for the house and then some. I also believe that the exposure this card is getting will be good for the industry.

Why? 

The card is getting a lot of attention worldwide and there may be people out there who gain a newfound respect for cards or collectibles. Some may even be inclined to jump into the hobby themselves.

What advice do you have for new card collectors?

My advice for people who are new to the hobby would be to do as much research as possible before you start spending large chunks of your collectibles budget. It's much easier and more feasible to do it for fun than it is to do it to invest. I wouldn't suggest looking at cards as an investment unless you become very knowledgeable of the industry or have expert guidance.

Were you ever able to geek out over sports cards with any of your teammates?

When I was playing, I'd get a lot of the stuff I bought shipped to the team facilities simply because there was always someone there to sign for it. The packages would end up in my locker and my teammates would see me opening them. This started a lot of great conversations and even got a few guys to jump into the hobby.

Anyone in particular?

When we were playing for Denver, Tyler Polumbus was someone who got it into cards pretty seriously with me.

Do you have a favorite card or set?

In my collection, my favorite card is a 1953 Topps Mickey Mantle PSA 10.  A dealer friend of mine found the card in a collection in Tucson, Ariz., and I was able to make a trip down there to see the card sitting in a binder before it was graded. The technology in 1953 wasn't incredibly efficient so a lot of the cards in that era came straight out of the packs off-center, mis-cut, and loaded with print defects. To see a card that not only managed to beat the odds out of the factory but also survive in flawless condition for 65 years is truly remarkable. To me, it's elite Americana and a beautiful piece of art that I can hold in my hand.

Is there a card that had eluded you so far that you'd like to own?

A 1952 Topps Mickey Mantle PSA 10.

Wait, isn't that the card you're selling? Is a PSA 10 that much different from a PSA 9? 

A PSA 10 1952 Topps Mickey Mantle is financially out of my reach. For most cards, PSA 10s are worth multiple what PSA 9s are. I don't know if I will ever be able to afford a 10 let alone convince the owner to sell it. But I'm not saying never.