CHARLOTTE – Linebacker Luke Kuechly took a major step forward Wednesday on his path back to the football field, participating in practice for the first time since suffering a concussion 20 days ago.

Kuechly remains in the concussion protocol, as do safety Kurt Coleman and cornerback Daryl Worley, who like Kuechly were limited practice participants. Their appearance on the practice field, however, means they could be cleared possibly as early as Thursday.

"All three are in the concussion protocol, but being on the practice field means they've moved to the next step," head coach Ron Rivera said. "Tomorrow morning will be very important when they visit with the medical staff."

Linebacker David Mayo, who like Worley went in the concussion protocol Sunday at Seattle, did not practice. Coleman sat out the Seattle game after going into the protocol at Oakland the week before.

Kuechly traveled to the West Coast for games at the Raiders and Seahawks but remained in the concussion protocol throughout the 10-day trip. He was injured in the second half of the Panthers' last home game, a November 17 victory over the Saints.

"He looked good," tight end Greg Olsen said. "He seemed to be in there a good amount running around. It was just nice to see him with a uniform on and a helmet on.

"Whether he plays or not, we have no idea, but just to see him out there is obviously a great step for him, and that's the biggest thing. It's not about the team. We all know how much we need him, but the best thing is just to see him back being himself and feeling good."

Defensive end Charles Johnson, who suffered a hamstring injury against the Seahawks, didn't practice. But defensive end Mario Addison, who didn't make the West Coast trip after injuring his foot against New Orleans, got in some work on the side though he didn't officially practice.

"It was good to see Luke and Kurt, and I got to watch Mario on the side work out a little bit to see how he was doing," Rivera said. "When guys get back out on the football field, it brings a little energy. It sparked a little energy in the defensive guys."