And so Rosner was understandably excited when he got wind of two basketball jerseys soon to sell at Sotheby’s. In an online sale running from March 12-26, the auction house will offer Michael Jordan’s signed “preseason debut” Chicago Bulls jersey, which the star wore in the 1984-85 preseason. And in a separate online sale running from April 10-24, it has Kobe Bryant’s “rookie debut” Los Angeles Lakers jersey, which the late player wore during the 1996-97 season. Each jersey is estimated to sell in the region of $10 million.

“They’re both certainly items that would meet my criteria,” says Rosner. “I mean, I love both those guys big time, and they’re both one-of-a-kind items.”

Whether or not the jerseys clear their estimates, the $10 million valuations are a sure sign that the collectibles market has entered a new phase, one where the ultrarare objects—often from players’ rookie seasons—have ascended to a distinct and lofty price stratosphere.

“You can have amazing athletes who are super loved and in demand, but their jerseys are not worth very much because there’s such a big population” of objects, says Brahm Wachter, head of modern collectibles at Sotheby’s. “The rarer things are, the more valuable they become. When you deal with rookie items, you’re dealing with one year in an athlete’s career, and then after that point it’s over.”

A Growing Divide

This relative scarcity of rookie items has become more pronounced as the sports memorabilia industry has matured and expanded. Wachter cites the increasingly prevalent practice of players wearing multiple jerseys a game so they have more “game-worn” jerseys to sell. “If every game the player is swapping jerseys, there’s a population of them and they’re being sold,” he explains. “If you think about rookie debut jerseys, that happens once. It’s not something that can be replicated. And so in that sense, they take on a certain importance.” A month after the rising star Victor Wembanyama made his debut with the San Antonio Spurs in October 2023, for instance, Sotheby’s sold the jersey from that first game for $762,000.

The phenomenon extends across sports. In 2022, Heritage Auctions sold a 1952 Topps Mickey Mantle rookie card for $12.6 million, making it the world’s most valuable sports card sold at auction. And last August, Heritage sold a 1954 Hank Aaron Milwaukee Braves rookie jersey—game-worn and signed—for a record $2.1 million. In that same auction, a 1911 rookie bat used by “Shoeless Joe” Jackson sold for $2 million. “We have seen a real surge in the last five years in the demand for basketball as the popularity and the international nature of the NBA continues to expand,” says Wachter. “But I would say that a lot of sports carry a ton of value.”

The enhanced import of the rookie category has become increasingly evident to Elliot Tebele, a 34-year-old digital media entrepreneur, who says he’s been collecting sports memorabilia since he was a child. Today he speculates that he has the world’s largest collection of Michael Jordan game-worn sneakers. “My favorite part of my collection is the early Jordan sneaker stuff,” he says. “That is the best of my collection, and almost the majority of my collection in terms of value.” Over the years, he says, that market has “drastically changed in terms of the values and competition.” 

Strong Growth

Both of the forthcoming jerseys at Sotheby’s encapsulate this change. The Kobe jersey, which was worn during his first game in both the regular season and preseason, last sold in 2012 for just $115,242. If it sells for its estimate, it would represent a roughly 8,600% increase in 13 years.

The Jordan jersey is the only photo-matched, game-worn jersey from his rookie season to ever come to auction. (Photo matching is the process of comparing pictures of the athlete wearing the jersey to the jersey itself, identifying small imperfections that authenticate the jersey.) It last sold in 2009 at a Basketball Hall of Fame auction for $50,000—and would represent a roughly 20,000% increase if it meets its estimate.

Rosner, for his part, is aware of the market’s upward trajectory, even if he says it’s not his primary concern. “If a picture is worth a thousand words, a ticket’s worth a million memories,” he says. “So if you have a jersey of somebody that you watched in the game, and maybe even during that game they said hi to you or gave you a high-five, the intrinsic value of that is so much deeper than just looking to buy something as an investment.”

That said, he concedes, “If I’m buying something, especially if it’s valuable, then I definitely hope that at some point down the road it’s worth more than what I paid for it.”