Minnesota Vikings quarterback Kirk Cousins was sent home from training camp with an undisclosed illness, coach Kevin O'Connell told reporters on Thursday.
Cousins missed a walk-through practice in the early afternoon at Eagan, Minn. The Vikings also were slated to hold a full practice later Thursday.
O'Connell said the team wasn't prepared to say if Cousins had COVID-19.
"We're still in that process of trying to go through all that," O'Connell said, "and make sure first and foremost: 'What are you feeling? What's going on?' And then going through our in-house process to make sure that if that does end being (COVID), we're on top of it.
"If not, there's still some other stuff going around that we want to make sure that we're being smart about for the other 90 players and the coaches."
Cousins missed a game late last season after testing positive for COVID-19.
The NFL stopped its COVID-19 protocol in March, but is still following CDC guidelines that call for five days in isolation after a positive test.
Kellen Mond and Sean Mannion are competing for the backup spot behind Cousins. Both quarterbacks figure to see plenty of action during Sunday's preseason opener against the Las Vegas Raiders.
Cousins, who turns 34 on Aug. 19, is entering his fifth season with the Vikings and 11th overall. He passed for 4,221 yards, 33 touchdowns and seven interceptions in 16 games last season.
Overall, he has thrown for 32,593 yards, 223 touchdowns and 91 picks in 125 games (120 starts).
--Field Level Media