The left knee that buckled and ended Benjamin's 2015 season during training camp in August was strong.
Benjamin's mental state was stronger.
"I'm going full speed on it," Benjamin said following Tuesday's practice. "You can't really hold back because if it gives out, it gives out. I just trust in the rehab that we did and feel comfortable with it."
Carolina's training staff recommended that Benjamin wear a knee brace, but the 28th pick of the 2014 draft would have none of it.
"The brace will be a mind thing," he said.
Having the 6-foot-5 Benjamin back will be a mind thing for opponents. Adding him to the league's top scoring offense last season (31.2 ppg.) can only make league MVP Cam Newton and others around him stronger.
"We can't count eggs before they hatch," Benjamin said. "But I think it will definitely be good having me back."
It can't help but be. Benjamin led all Carolina wide receivers with 73 catches for 1,008 yards and nine touchdowns during his rookie season. He added 11 catches for 108 yards and two touchdowns in two playoff games.
He easily was Newton's top target outside of tight end Greg Olsen. Opposing teams had no real answer for a player of Benjamin's rare size and speed.
"In football you can never have enough good players, and enough good players that understand how they fit into the big picture," Olsen said. "That's always the million dollar problem, is you can have a lot of good players but everybody is not necessarily willing to accept where they fit into the team aspect of offense.
"Kelvin is a rare guy. He's a No. 1 talent with No. 1 production that understands how he fits into the whole big picture. Anytime you add guys like that to a team you can't help but improve."
The Panthers actually flourished offensively after Benjamin went down because Newton started spreading the ball around more. The Panthers had five players with 31 or more catches, two more than the year before.
Newton had 35 touchdown passes last season, 17 more than he had in 2014.
"One of our greatest strengths as an offense last year was the versatility," Olsen said. "At the same time, the ability to just play a role by that wide receiver group, that was a catalyst for our season developing the way it did.
"Adding Kelvin to that is just going to help.
As general manager Dave Gettleman has reminded often, the return of Benjamin is like getting an extra first-round draft pick.
Stephen Hill, who also suffered a season-ending ACL tear in training camp, is back. The Panthers believe the 2012 second-round pick by the New York Jets can flourish in a system that doesn't depend on him being the star.
Those options with everyone back from a ground game that ranked among the top five in the league makes this offense scarier than ever.
"That's the beauty of getting Kelvin back," Carolina coach Ron Rivera said. "Now all of a sudden you throw that other guy into the mix and everybody's going to go, 'How do we defend that?'"
Benjamin won't be turned completely loose until training camp. For now, Rivera is comfortable with his star receiver participating in individual drills and watching the team drills.
He didn't rule out Benjamin wearing a knee brace once he has to go live against defenders -- just as a precaution.
Meanwhile, Benjamin isn't worrying about the knee.
"I try not to baby it," he said. "I try to go hard. Whatever the route is, I try to trust in the process that we have been doing, the rehabbing. So I just go ahead and make that plant."