Grant Wahl, an American soccer journalist known for his opposition to hosting the FIFA World Cup in Qatar, has died while covering a match in Doha. He was 48.

Wahl reportedly collapsed in the press box while covering the Argentina-Netherlands match at Lusail Stadium on Friday.

Paramedics performed CPR at the scene before taking him away on a stretcher.

The US State Department said American authorities have been "in close communication" with his family.

'My brother was healthy'

Wahl made international headlines in November when he was denied entry to the United States' first match in Qatar because he was wearing a rainbow shirt in support of the LGBT community.

The journalist's brother Eric Wahl, who is gay, said he suspects foul play.

"I'm the reason he wore the rainbow shirt to the World Cup," he said in a video posted to Instagram shortly after his brother's death.

"My brother was healthy. He told me he received death threats. I do not believe my brother just died. I believe he was killed. And I just beg for any help."

Wahl's wife, renowned infectious disease expert Celine Gounder, tweeted: "I'm in complete shock."

Earlier this week, Wahl said on several platforms that he was feeling ill.

"My body finally broke down on me. Three weeks of little sleep, high stress and lots of work can do that to you," he wrote in a Substack newsletter earlier in the week.

"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. I didn't have COVID (I test regularly here), but 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"

Tributes flow for Wahl

Wahl was a Sports Illustrated journalist for 26 years who later moved to Substack and ran his own successful soccer podcast.

He is credited with helping boost the profile of soccer in the US.

"The entire US Soccer family is heartbroken to learn that we have lost Grant Wahl," the country's soccer federation posted on Twitter.

"Fans of soccer and journalism of the highest quality knew we could always count on Grant to deliver insightful and entertaining stories about our game, and its major protagonists: teams, players, coaches and the many personalities that make soccer unlike any sport."