SANTA CLARA, Calif. (AP) — A man who suffered a heart attack during the San Francisco 49ers' debut game at Levi's Stadium has died.

The Santa Clara Fire Department said stadium staff responded to a cardiac emergency during the third quarter of the 49ers' preseason opener against the Denver Broncos on Sunday.

The man received CPR and was rushed to a hospital, where he was pronounced dead. His name was not released.

The 49ers issued a statement Sunday night offering condolences to his family and friends.

The team's 34-0 loss to the Broncos and 80-degree heat drove thousands of fans to leave the new stadium midway through the game.

Team officials told the San Jose Mercury News ( there was an unusually high number of calls for emergency services, likely because of the heat.