Garrett did not come in for Wednesday's practice after reporting not feeling well. Garrett will not play against the Eagles.
"Yeah, he is a good player," said Browns coach Kevin Stefanski of Garrett. "We know that. We do not want to be without him, but we are. And I promise you the guys will be ready to go."
The team announced that a player had tested positive for COVID-19 and that "zero high-risk contacts have been identified."
Browns right tackle Jack Conklin and kicker Cody Parkey were placed on the reserve/COVID-19 list earlier this week after coming into contact with an outside practitioner who had tested positive. Coach Kevin Stefanski has said he was hopeful that both will be able to rejoin the team before Sunday.
Losing Garrett for Sunday's game is a huge blow to the Browns, who at 6-3 are aiming to snap the NFL's longest playoff drought of 18 years.
Garrett leads the league with 9.5 sacks; the rest of the team combined has only 12.5 sacks. Garrett also has an NFL-best four forced fumbles.
According to league rules, a player who tests positive for COVID-19 can't return to the team until at least 10 days after the start of symptoms, plus at least 24 hours after symptoms have passed.