Quickley said tongue-in-cheek on Thursday after the game that he's been taking the pandemic so seriously that he even showers with a mask on.
It's unknown at this point if Quickley had a positive test, or if it's precautionary.
If Quickley is out for an extended period of time, Miles McBride could continue to get minutes, especially if Derrick Rose's ankle still isn't healthy.
McBride took the most out of his opportunity on Thursday, playing in almost 36 minutes and scoring 15 points and dishing out nine assists.
Quickley is averaging 10.2 points on 39 percent shooting in 24 games this season.
The Knicks will be in Boston to take on the Celtics on Saturday night.