"The biggest thing was when Charles came in and met with us, the passion with which he talked about wanting to be with us was awesome," coach Ron Rivera said Monday from the NFL owners meeting. "I wish the other players could all hear the way he talked about it.
"To me it was really a profound statement that he made."
Johnson, 29, was released March 3 so the NFC champion Panthers could clear $11 million under the salary cap. Scheduled to count $15 million under the 2016 cap before being cut, he signed a one-year, $3 million deal to return less than a week later.
He did this despite having an offer for at least one multi-year deal for twice that.
Rivera called Johnson's decision rare in a league in which players typically look for the big deals. Others at the owners meeting agreed.
"I'd like to see it become more of the norm," Rivera said of Johnson, who signed a six-year, $76 million deal with Carolina in 2011.
With Johnson, Rivera likes where Carolina is as the defensive end position heading into 2016. Johnson and Kony Ealy, who had three sacks in Super Bowl 50, are the incumbent starters. Behind them is pass-rushing specialist Mario Addison, Ryan Delaire, Wes Horton, Arthur Miley and Larry Webster.
Rivera likes the potential of players such as Delaire, Miley and Webster.
Rivera admitted the team needs to add another end for the "future" with Johnson approaching 30 and signed for only one year.
"But going forward, do we have to draft that guy?" Rivera said. "I don't know."
The Panthers have the 30th overall pick. Defensive end would have been a priority had Johnson not re-signed.
Johnson's unselfishness not only gave general manager Dave Gettleman more room to maneuver financially, it gave him more flexibility in the draft.
"Do we have a group of guys we like? Yes," Rivera said of the end position. "It's a good group. Charles adds stability to that position we were looking for.
"In talking to Dave, we've got to look at the defensive tackle spot as well. I know Dave has some ideas already."
The Panthers want to sign Pro Bowl defensive tackle Kawann Short to a long-term deal, preferably before he enters the final year of his rookie deal in 2016.
They also have to make a decision on whether to put the fifth-year option on tackle Star Lotulelei, a first-round pick in 2013.
They recently signed veteran Paul Soliai to a two-year deal in free agency, but that still leaves an opening in Carolina's four-man rotation at tackle.
Rivera said that player could come in the draft or free agency.
Again, because of Johnson's willingness to take a huge cut and return the Panthers have the option in a tackle-deep draft.
"What's really neat about it," Rivera reiterated, "was the conversation he had with us."