Under Armour founder Kevin Plank is back as CEO, abruptly ending Stephanie Linnartz’s three-year turnaround plan two years early

Linnartz, a veteran executive who was previously No. 2 at Marriott International, left the global hotel chain last year to become CEO of Under Armour. She took over the struggling sportswear chain on Feb. 27, 2023—and, the company said today, she will be leaving the CEO role at the end of this month, after just over a year on the job. She had said that her turnaround strategy for the company would take three years to execute.

Kevin Plank, Under Armour’s controversial founder and controlling shareholder, will again become its CEO, starting April 1. The latest “boomerang” CEO to return to his former job (a group that includes Disney’s Bob Iger and Howard Schultz of Starbucks) will become his company’s fourth CEO in four years. He first “stepped down” from the job in January 2020 to become executive chairman, and he continues to own 65% of the company’s voting shares. 

Under Armour did not give a reason for the abrupt CEO change, and a spokesperson declined to comment. In a LinkedIn post, Plank thanked Linnartz for her contributions towards Under Armour: “She helped advance the company forward in many important ways, including elevating our leadership talent in product, design, supply chain, consumer loyalty, and regional management,” he wrote. “Much work still needs to be done, but her leadership helped put us on the right track toward winning.”

Running Under Armour was always going to be a turnaround job–which Linnartz went into with eyes wide open. “I believe in taking calculated risks,” she told me last summer, when I profiled her for Fortune. 

“She has hit the ground running, launching a clearly articulated three-year strategy that sets us up for strategic growth,” Plank told Fortune, in an emailed comment, at the time. “I could not be more excited to have her at Under Armour and to work with her every day.” 

But the challenges Linnartz faced were steep: Under Armour has struggled to grow revenue or profits since its early heyday. Its share price has plummeted since its 2015 peak, and retail experts call its brand identity muddled, at best.

Meanwhile, Plank’s politics and personal life have continued to put his company into sometimes-unflattering headlines. And Plank had remained an unavoidable presence at the company well after his departure from the CEO role, as I saw when I visited the company’s headquarters in August—where I was regaled several times with the story of how Plank started the company in his grandmother’s basement in 1996:

“Buildings and apparel lines are numbered either 96 (for the year he founded Under Armour) or 37 (for the number of KP’s college football jersey),” I wrote then. “One corridor at headquarters is decorated with an enormous photo of that jersey, next to blown-up versions of Plank’s early Under Armour business cards, next to #inspo phrases like ‘HUMBLE & HUNGRY BEGINNINGS.’” 

The visible ongoing presence of a charismatic founder can be a problem for a new CEO, says Neil Saunders, a GlobalData Retail analyst who covers Under Armour. “Despite the fact that someone else is CEO, Kevin Plank is still there,” he says. “It is still a very founder-led company … and most CEOs don’t want backseat drivers.”

While Linnartz had hired several new senior executives and launched a rewards program to increase customer loyalty, her strategy had not yielded immediate results: Under Armour’s most recent quarterly revenues fell 6 percent from a year earlier. 

“She inherited a brand that always had a lot of problems,” says Saunders. “And a year is really not enough time to make a change.”

Investors at first cheered Plank’s return: The company’s shares rose in after-hours trading, before sliding back down. Under Armour also announced that, as Plank becomes CEO, Mohamed A. El-Erian, the former PIMCO CEO, will become the non-executive chair of its board.

“As I look back at my past year at Under Armour, one of the things I am most proud of is the excellent talent we have brought into the organization,” Linnartz wrote in an email to Under Armour employees. She added that she wishes Plank, “the executive leadership team and all of you much success in the years ahead.”

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