"It could be No. 1," Cason said of the Panthers.
Cason knows what a top-ranked defense looks like. He played for one in San Diego in 2010 when Carolina coach Ron Rivera was the defensive coordinator for the Chargers.
Cason says while the personalities on Carolina's defense are different, many things are the same.
"Everyone is together," he said after a rain-soaked practice on Thursday. "Everyone picks each other up. Everyone hustles and does what they need in this defense to make it work."
Cason is one of the new pieces to the defense, which lost three starters in the secondary, two to free agency. He was signed as a free agent from Arizona where he was reverted to a backup after starting 45 games the previous three seasons with San Diego.
One of the few plays he made last season was against Carolina, returning a Cam Newton fumble 43 yards in a 22-6 victory over the Panthers in Week 5. He doesn't give Newton any ribbing about the fumble, and insists the Carolina quarterback hasn't ribbed him because he ran him down for the tackle.
"We don't talk about that," Cason said.
But Cason has been something to talk about in training camp. Brought in to replace Captain Munnerlyn, who signed with Minnesota, he looks more like the player San Diego took with the 27th pick of the 2008 draft making interceptions and batting down passes.
"This defense is very similar of course to what we did," Cason said. "But personnel wise, everybody is a different guy except me."
Cason insists Rivera is the same person now as he was as a coordinator, which is one of the reasons Carolina was such an attractive landing spot for this player who spent basically his entire college and NFL career on the West coast.
"He's a former player as well, so he definitely understands us as players," said Cason, who also has reunited with secondary coach Steve Wilks, a member of Rivera's San Diego defensive staff. "The communication between coach and players is awesome, and that's what I think he does very well."
At 6-foot-1, Cason stands well above the 5-8 Munnerlyn. He's part of a movement toward bigger cornerbacks like the Seattle Seahawks had in winning the Super Bowl.
Seattle, by the way, finished with the league's top defense in 2013.
Cason could be one of the pieces to help Carolina, which returns all of one of the league's top front sevens, reach that point.
"I bring the mindset to get that done," he said. "I'm part of it now, so I'm very excited to see it get there."