Grant Wahl, an American journalist who helped grow the popularity of soccer in the U.S. and reported on some of the biggest stories in the sport, died Saturday while covering a World Cup match between Argentina and the Netherlands. He was 49.

Wahl fell back in his seat in a section of Lusail Stadium reserved for journalists during extra time of the game, and reporters adjacent to him called for assistance.

Emergency services workers responded very quickly, treated him for 20 or 30 minutes on site and then took him out on a stretcher, said Keir Radnedge, a veteran British sports journalist who was working nearby at the time.

The World Cup organizing committee said he was taken to Doha's Hamad General Hospital, but it did not state a cause of death. “We are in touch with the US Embassy and relevant local authorities to ensure the process of repatriating the body is in accordance with the family’s wishes,” it said in a statement.

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Wahl, who wrote for Sports Illustrated for more than two decades and then started his own website, was a major voice informing an American public of soccer during time of increased interest after the U.S. hosted the 1994 World Cup. He also brought a critical eye to the organizational bodies of the international sport.

Wahl attempted to run for FIFA president against Sepp Blatter and Mohamed bin Hammam in 2011. He promised to open FIFA to greater transparency and said he contacted 150 countries without winning support for a nomination.

He “really helped put soccer on the mainstream sports map in the States,” Radnedge said.

“Grant had a strong moral compass, on where sports should be and how sport ... should help set standards for people,” he said. “There was never any doubt that Grant was on the side of the good guys in wanting soccer to make the best of itself.”

Wahl was covering his eighth World Cup. He wrote Monday on his website that he had visited a medical clinic while in Qatar.

“My body finally broke down on me. Three weeks of little sleep, high stress and lots of work can do that to you,” Wahl wrote. “What had been a cold over the last 10 days turned into something more severe on the night of the USA-Netherlands game, and I could feel my upper chest take on a new level of pressure and discomfort.”

Wahl wrote that he tested negative for COVID-19 and sought treatment for his symptoms.

“I went into the medical clinic at the main media center today, and they said I probably have bronchitis. They gave me a course of antibiotics and some heavy-duty cough syrup, and I’m already feeling a bit better just a few hours later. But still: No bueno,” he wrote.

Wahl tweeted on Wednesday that he had celebrated his birthday that day.

“We could always count on Grant to deliver insightful and entertaining stories about our game, and its major protagonists,” the U.S. Soccer Federation said in a statement. “Grant's passion for soccer and commitment to elevating its profile across our sporting landscape played a major role in helping to drive interest in and respect for our beautiful game."

Wahl's wife, Dr. Celine Gounder, tweeted that she was thankful for the support of her husband’s “soccer family” and friends who had reached out.

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“ I’m in complete shock,” wrote Gounder, who is an associate professor at New York University School of Medicine, an attending physician at Bellevue Hospital Center and a CBS News contributor.

U.S. State Department spokesman Ned Price said in a tweet that American officials were in touch with Qatari authorities “to see to it that his family’s wishes are fulfilled as expeditiously as possible."

Wahl wore a rainbow T-shirt in support of LGBTQ rights to the United States' World Cup opener against Wales on Nov. 21 and wrote that security refused him entry and told him to remove the shirt. Gay and lesbian sex is criminalized in Qatar, a conservative Muslim emirate.

Wahl wrote he was detained for 25 minutes at Ahmed Bin Ali stadium in Al Rayyan, then was let go by a security commander. Wahl said FIFA apologized to him.

Among Wahl’s work before he began covering soccer exclusively was a Sports Illustrated cover story about LeBron James in 2002, when James was a junior at St. Vincent-St. Mary High in Akron, Ohio.

“He was always pretty cool to be around. He spent a lot of time in my hometown of Akron,” James said in Philadelphia after the Los Angeles Lakers lost in overtime to the 76ers. “Any time his name would come up, I’ll always think back to me as a teenager having Grant in our building down at St. V’s. It’s a tragic loss. It’s unfortunate to lose someone as great as he was. I wish his family the best. May he rest in paradise.”

A voter at times in FIFA’s annual awards, Wahl was among 82 journalists honored last week by FIFA and the international sports press association AIPS for attending eight or more World Cups.

“His love for football was immense and his reporting will be missed by all who follow the global game,” FIFA president Gianni Infantino said in a statement.

Wahl graduated from Princeton in 1996 and worked for Sports Illustrated from 1996 to 2021, known primarily for his coverage of soccer and college basketball. He then launched his own website, Fútbol with Grant Wahl, and a podcast with Meadowlark Media.

Wahl also worked for Fox Sports from 2012-19 and was hired by CBS Sports in 2021 as an analyst and editorial consultant. Wahl wrote the 2009 book “The Beckham Experiment” after English soccer star David Beckham joined Major League Soccer’s LA Galaxy, and the 2018 book “Masters of Modern Soccer.”

His death at the World Cup left fellow journalists covering the games stunned.

“You come to a World Cup as a journalist to work, to share the stresses, the pressures but also the enjoyments and the fascination of it — and to share that with your readers, your listeners, your viewers. That’s what Grant was doing, that’s what he enjoyed doing. Everybody recognized that enthusiasm in him,” Radnedge said.

“So for him to not be with us anymore at such a young age, that’s an immense shock.”