In the summer of 2018, two top Under Armour executives traveled to the West Coast on a critical mission. Kevin Plank, the sports apparel company’s founder and chief executive, and Patrik Frisk, its president and chief operating officer, needed to persuade Stephen Curry, the Golden State Warriors star and the company’s highest-profile endorser, not to leave the brand.

The two sides had grown increasingly frustrated with the relationship, said two former Under Armour executives familiar with the matter, who spoke on condition of anonymity to discuss the previously undisclosed meeting. In 2017, Mr. Curry took public exception to a comment by Mr. Plank calling President Trump “a real asset” to the country, prompting the executive to take out a full-page newspaper ad to explain what he said about Mr. Trump “did not accurately reflect my intent.”

But the relationship between the two remained tense. Mr. Plank was unhappy that Mr. Curry, whose endorsement deal pays him millions of dollars a year, would rarely wear Under Armour clothing to N.B.A. games. Mr. Curry was upset that sales of the signature Curry 3 shoe had been weak.

At the meeting, participants found a solution that would showcase just how much Mr. Curry meant to the company. Mr. Plank and Mr. Frisk agreed to build a separate business around him, one reminiscent of what Nike had done for Michael Jordan two decades before. The company brought on the former executive who had overseen the creation of the Jordan brand at Nike to run the Curry brand and promised Mr. Curry much more involvement in the development of his shoes. Mr. Curry decided to remain, and a crisis was averted.