ESPN's Adam Schefter first reported the news on Saturday.
Drew Lock and Brett Rypien have been deemed "high-risk, close contacts" and will be unable to play. ESPN's Jeff Legwold reported that Denver sent the two home from practice Saturday—along with practice squad QB Blake Bortles—out of caution.
Mike Klis of 9News reported third-string running back Royce Freeman is the team's emergency quarterback.
The Broncos added quarterback Jeff Driskel to the team's reserve/COVID-19 list Thursday, ruling him out for the game as well.
A positive test within the organization prompted Denver to shut down its team facilities from Thursday to Saturday. The Broncos canceled practice Friday despite getting clearance from the league.
"It was our choice, my choice, to not practice [Friday]," head coach Vic Fangio said, per Legwold."I just felt having two consecutive days with a positive test each day, that I just felt like we needed to not practice."
Fangio was hopeful the league would clear the remaining active QBs, telling reporters he didn't have concerns because the players hadn't experience prolonged contact with each other. That's now moot.
Schefter noted the Saints are en route to Denver and are acting as though the game will be played Sunday. Kickoff is slated for 4:05 p.m. ET.