Topps has been synonymous with trading cards, particularly baseball cards, for 70 years.

That era will soon be over. Major League Baseball and the Major League Baseball Player’s Association are ending their licensing agreement with Topps in favor of a deal with Fanatics, the up-and-coming sports collectible brand. The loss of baseball rights also led to the abrupt cancellation on Friday of a plan for Topps to go public, casting its future into question.

The company, which also owns Bazooka gum, announced a deal in April to merge with a special purpose acquisition company, or SPAC, run by Mudrick Capital. The $1.3 billion merger was set to go to a shareholder vote next week.

Topps and Mudrick announced Friday morning that the deal is off, the day after they were notified that the baseball contracts would not be renewed when they expire in 2022 for players’ images, which are controlled by the players’ union, and 2025 for team logos, which are controlled by M.L.B.

Topps has been owned by Tornante, the investment firm of the former Walt Disney Company chief Michael Eisner, and the private equity firm Madison Dearborn since 2007, when the two acquired it for $385 million.

Fanatics, most recently valued at $18 billion, has been drawing on its ties to major sports league teams to expand beyond hats, hoodies and other branded merchandise. In June, it started a digital collectibles firm called Candy Digital, which has partnered with M.L.B. to introduce a series of nonfungible tokens. Fanatics has also poached a number of executives from sports teams, gambling companies and tech firms as it considers expanding into ticketing, betting and gambling.

The baseball deal reflects Fanatics’ growth ambitions, moving into the baseball card market at a time when they have exploded in popularity, amid growing interest from homebound traders and digital investors buying NFTs.

Fanatics will create a new trading card company and give both M.L.B. and the players’ union seats on the board, said a person familiar with the plans who spoke on condition of anonymity because those plans were not yet public. The union and M.L.B. will get a stake in the company, a shift to owning a piece of the company that makes money from its members’ images rather than simply licensing those images. Sports unions have in recent years bolstered their commercial arms to help players earn more from their likenesses.

Riding high on its new licensing deals, Fanatics could consider trying to acquire one of the three major card companies: Panini, Upper Deck or Topps, a person familiar with the company’s thinking said. That would mirror its strategy with the apparel company Majestic, which it acquired after winning the rights to make uniforms for M.L.B. that Majestic previously held.

Kevin Draper and Ephrat Livni contributed reporting.