Grant Wahl, an esteemed American sports journalist best known for his soccer reporting with a focus on storytelling and behind-the-scenes coverage of the rise of the sport in the United States, died at the age of 49 early Saturday in Qatar. Wahl collapsed suddenly while in the press box of Lusail Stadium during the Argentina-Netherlands quarterfinal match. He may have suffered a heart attack or a pulmonary event, according to those close to the situation, but the exact cause of death is not yet known, CBS News reports.

Wahl was an analyst on CBS Sports HQ throughout the 2022 FIFA World Cup in Qatar and wrote guest columns on CBS Sports that focused on the United States men's national team. He was also an editorial consultant for soccer documentaries on Paramount+.

CBS Sports issued the following statement: "We are deeply saddened by the sudden and tragic passing of Grant Wahl. Grant was an exceptional journalist and a tremendous friend, colleague and ambassador for the game of soccer. Grant's impact and imprint on the soccer community within the U.S. and globally will endure for years to come. All of us at CBS Sports offer our heartfelt condolences to Grant's wife, Dr. Celine Gounder, his family and friends."

Wahl, who was covering his eighth World Cup, wrote on his personal Substack about a recent medical incident he experienced 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. 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 on Dec. 5.

"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."

Wahl's agent, Tim Scanlan, told CBS News that Wahl "appeared to have suffered some sort of acute distress in the press room" when the two teams began playing in extra time. Paramedics were called to the scene and brought him to "a nearby hospital."

Born in Mission, Kansas, Wahl graduated from Princeton University in 1996. While at Princeton, he covered the Tigers men's soccer team coached by Bob Bradley, who would go on to coach the United States men's soccer team a decade later.

Wahl fortified his place in the sports industry as one of the most renowned soccer reporters in the United States where he covered Major League Soccer, the National Women's Soccer League and the U.S. national teams. He worked his way up to become a senior writer at Sports Illustrated where he covered numerous NCAA Tournaments, Olympics Games and World Cups over the course of his career.

Following the boom from David Beckham's surprise arrival to the Los Angeles Galaxy in 2007, Wahl published his first book, "The Beckham Experiment," in 2009. Detailing impact of Beckham's move to the United States, it became a New York Times bestseller. 

Wahl followed with "Masters of Modern Soccer: How the World's Best Play the Twenty-First-Century Game," a book that gave a behind-the-scenes perspective on how elite players (Christian Pulisic and Javier Chicharito) and coaches (Roberto Martinez) strategize on and off the field to execute in high-pressure situations.

Wahl brought his day-to-day news coverage to Substack during this World Cup cycle where he was on site for every game. He also had a renowned podcast, "Fútbol with Grant Wahl," on which he provided analysis, expertise and reporting on soccer's top stories alongside co-host Chris Wittyngham. On Thanksgiving Day, "Good Rivals" -- a docuseries exploring the social, political and sporting layers of the rivalry between the United States and Mexico -- launched with Wahl as one of the producers. 

While in Qatar, Wahl was honored by FIFA -- along with 70-plus veteran journalists who have covered eight or more World Cups -- in a special ceremony held in conjunction with the International Sports Press Association (AIPS). He received a mini-replica of the FIFA World Cup trophy from two-time Brazil World Cup winner Ronaldo during the Monday ceremony.

Wahl served as a watchdog for the sport, and he was integral to the rise of soccer in America, especially following the 1994 World Cup in the United States and the launch of MLS in 1996. There weren't many on-site storytellers providing behind-the-scenes insight on American soccer quite like Wahl.

In 2011, he briefly campaigned against the presidency of Sepp Blatter at FIFA in an effort to shine a light on changes that needed to be made to the governing body of the sport.

Wahl is survived by his wife, Celine Gounder, an American medical doctor and medical journalist who specializes in infectious diseases and global health. She is a CBS News medical contributor and former member of the COVID-19 Advisory Board created by the transition team of then-U.S. President-Elect Joe Biden.

U.S. Soccer released the following statement:

"The entire U.S. Soccer family is heartbroken to learn that we have lost Grant Wahl. 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. Here in the United States, 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. As important, Grant's belief in the power of the game to advance human rights was, and will remain, an inspiration to all. Grant made soccer his life's work, and we are devastated that he and his brilliant writing will no longer be with us. U.S. Soccer sends its sincerest condolences to Grant's wife, Dr. Celine Gounder, and all of his family members, friends and colleagues in the media. And we thank Grant for his tremendous dedication to and impact on our game in the United States. His writing and the stories he told will live on."