Coach Ron Rivera said the team's sack leader this year and the past three seasons will spend what is an off weekend for players getting treatment. He remains optimistic that Johnson will be ready for the Nov. 3 game against Atlanta.
Johnson went down with 1:08 left after Tampa Bay got an extra possession because the Panthers (4-3) failed to recover an onside kick. Rivera said the turf at Raymond James Stadium may have contributed.
Johnson already had two sacks in the game to increase his season total to six. He has been Carolina's leader in sacks the past three seasons with 12.5 a year ago, 9.0 in 2011 and 11.5 in 2010. He has 49 career sacks.
"So far it's positive,'' Rivera said of the early diagnosis. "A lot depends on how sore he is the next couple of days.''
Running back DeAngelo Williams suffered a quad injury, but Rivera expects him to be ready for the Falcons. Rivera added the expected return of Jonathan Stewart from an ankle injury that has had him on the physically unable to perform list the first seven games won't be a factor.
The plan remains to put Stewart through a hard workout on Monday and, if there are no setbacks, activate him for the Falcons.
"The nice thing about it is we have a guy that is hungry, fresher, and who could come in and give an extra spark,'' Rivera said.