The Detroit Lions have placed quarterback Matthew Stafford on the reserve/COVID-19 list. Stafford is now the eighth Lions player to receive the designation.

Matthew Stafford, Coronavirus, COVID-19Leon Halip / Getty Images

The exact reason why Stafford was placed on the list was not revealed; however, the label is given to any player who tests positive for COVID-19 or have been in close contact with someone who has the coronavirus. The Lions performed a third round of tests, Friday.

The NFL and NFLPA have agreed on a policy that states "clubs are not permitted to comment on a player's medical status other than referring to roster status."

In May, Stafford said he plans to be as cautious as possible, considering he has a pregnant wife at home:  "I think it's in everybody's best interest to be as safe as you can possibly be whether you've got a pregnant wife at home with kids or not," Stafford said. "Obviously nobody really knows, there's not hard data on this yet, on what it does to a pregnant woman or a baby or whatever it is. We're just trying to make sure we're doing whatever we possibly can to limit our exposure.

"Make sure we are at home doing everything that the experts are telling us to do, as much as we possibly can, and we're trying to stay sane and still have a little bit of fun here and there."