Johnston (chest) wasn't practicing during the portion of Friday's session open to the media, Noah Furtado of The Athletic reports.
With Johnston having been limited Wednesday and Thursday, this could be more of a rest day for the wideout. The winless Chargers appear set to head into Sunday's game against the Broncos without Ladd McConkey (foot) after he missed practice all week, so Johnston is going to be needed alongside Tre' Harris at wide receiver.