Real Salt Lake trading cards? Who knew? But this passionate RSL fan is all over it.

Inside a blue 4-by-4-foot safe with an electronic lock, Robert Kreib keeps his most prized collection of Real Salt Lake memorabilia.

While he proudly displays his framed Nick Rimando jersey; various captain armbands and goalie gloves; and myriad soccer balls, pairs of cleats and season ticket stubs — all of which are signed — in the basement of his Saratoga Springs home, Kreib keeps this particular collection hidden from plain view. There’s just too many of them and they’re too valuable to risk having them out.

They’re even protected inside the comforts of the metal safe, housed inside a rectangular box and shielded from the elements and smudgy fingerprints by thin plastic sleeves or thick plastic cases.

Kreib collects RSL trading cards. He has about 1,000 of them, and they depict players from every era. He has cards of Eddie Pope, Jason Kreis, Álvaro Saborío, Javier Morales, Kyle Beckerman, Nick Rimando, Albert Rusnák and many in between.

The world of trading cards is a robust one — just not for Major League Soccer, which is not as ubiquitous as other sports leagues in the United States such as the NBA, MLB or NFL. Those who collect them, Kreib said, do so mostly out of deep passion.

“There are a few people out there who do it to make money because that's what they do,” Kreib said. “But 99% of them, they're going to lose money. It's just for their own enjoyment and it's a labor of love for them because they're a diehard fan of whatever that local team is.”

Kreib is one of those diehard fans. He’s an RSL season ticket holder and has been for several years. He even used to sit on the fan council that regularly meets with the club’s front office.

Kreib is also a diehard collector. Other than himself, there are just two other individuals that collect RSL cards, and only one of them is a Utah resident, he said.

Kreib started collecting RSL cards about eight years ago. But he’s been a collector of various types of memorabilia since he was a child. It started with basketball and football cards, then transformed into getting his hands on every Metallica CD he could find, including the rare and imported ones.

After selling his Metallica collection, Kreib started one with action figures he loved from his childhood. He said the collection was “over” the level of Steve Carell’s character in “The 40-Year-Old Virgin,” who had an apartment-filling memorabilia collection his friends urged him to hide before a big date with Catherine Keener’s character.

Kreib’s RSL collection started when he moved to his current home with his wife of almost nine years. He’s acquired most of his rarest cards — the ones of which only one exists — in his personal collection by buying or trading for them. The most he’s ever paid for a card he coveted is between $200 and $300, which is on the low end compared to other MLS teams, he said.

But sometimes Kreib will get lucky and pull a rare RSL card while opening a new box, which he often does online with other collectors on a Facebook group he started. One Christmas, he was opening a box his wife gave him as a gift and he pulled a one-of-a-kind Nick Rimando card.

“I was screaming like a kid on Christmas who opened his favorite toy,” Kreib said.

The odds are getting a one-of-a-kind in that fashion is extremely difficult, Kreib said. It’s not just that only one exists. A collector has to open several hundreds packs, which hold varied numbers of single cards, to find one.

“It’s like playing the lottery or gambling,” Kreib said.

While that Rimando card is Kreib’s favorite of his uniques, he’s also partial to the cards that include an actual piece of a player’s jersey. One such card he has in his collection is a one-of-a-kind of Rusnák and Joao Plata featuring pieces of both players’ jerseys. He acquired that one from a friend in Portland.

And there’s only six of a certain card that features a CONCACAF jersey worn by Beckerman. Kreib has three of them.

With so many cards in his collection — and so many he’s still yet to get — Kreib needs an organization system. His boxes are separated by year and set. He has pictures of all his cards in Google Photos on his phone. And, he uses Evernote, an organization app, to keep track of the cards he still needs for his collection.

That seems complicated, but it’s how Kreib operates.

“I’m one of those analytical people,” Kreib said. “I like to have a spreadsheet and I’m well-organized. That gives me peace. That’s like my Zen thing — organizing, collecting and arranging.”

Kreib makes appearances at RSL training sessions periodically if he has cards for the players to sign. Sometimes, if he doesn’t need a card, he’ll give it a player as a gift.

“It's a little something I can do to give back to them for signing for me,” Kreib said.

Beckerman said he puts away the cards Kreib gives him for safe keeping and likes that gives cards away to players.

“I think that’s a neat thing that he does,” Beckerman said.