SPARTANBURG, S.C. (AP) Well, it turns out that maybe Panthers four-time All-Pro middle linebacker Luke Kuechly may have a minor flaw in his game.

Who knew?

The 27-year-old Kuechly, considered one of the best players in the league at his position, said after Sunday's practice his pass rushing ability needs to improve ''by leaps and bounds.''

And Panthers coach Ron Rivera was quick to agree.

''Yes, he does'' need to improve, Rivera said. ''Like Cam (Newton) likes to tell you, `Superman has his Kryptonite.'''

Kuechly has been akin to Superman for the Panthers defense over the past six seasons.

He has 818 tackles and 15 interceptions during that span, and has staked his claim as the most productive middle linebacker ever to play for the Panthers -with a realistic chance to go down as one of the NFL's all-time bests along with Ray Lewis, Jack Lambert, Dick Butkus and Mike Singletary.

Rivera has repeatedly said Kuechly is like having a coach on the field with his ability to call out an opponent's play call to teammates before the ball is ever snapped. He's seemingly always around the ball and his mistakes are few and far between.

Getting to the quarterback has rarely been one of Kuechly's strengths.

He has 10+ career sacks, including just one last season. By comparison, Seattle middle linebacker Bobby Wagner - whom Kuechly is often compared to in the NFC - has 15+ sacks during that same span.

Kuechly is working with new linebackers coach Steve Russ to improve his explosiveness and ability to penetrate the line of scrimmage, a skillset that could potentially elevate the 2013 NFL Defensive Player of the Year to a whole new level.

''Coach Russ has a planned attack for (improving) that and hopefully it will translate into a game,'' Kuechly said.

Kuechly joked that he has to get better at pressuring the quarterback because his longtime buddy Thomas Davis, the team's outside linebacker, ''beats me in that (category) every year - and I have to try to get him back.''

This may be Kuechly's year to get the best of Davis, who will start the season serving a four-game suspension for testing positive for a banned substance.

It's not anything new for Kuechly to target an area to improve. For the past couple of years Kuechly spent extra energy working on his pass coverage skills, an area in which he has shown noticeable improvement.

Of course, the biggest concern for Kuechly will be avoiding another concussion. He has sustained a concussion in each of the past three seasons, causing him to miss 10 games.

The Panthers simply can't afford to lose him.

His speed and ability to chase down ball carriers from sideline to sideline still amazes Rivera, who played linebacker for nine seasons for the Chicago Bears and won a Super Bowl in the 1985 season.

Rivera said he's ''seen everything'' from Kuechly, but pointed to a play he made last week in practice that caused the coach to pause the game film and replay it in slow motion several times. As Rivera describes it, Kuechly was chasing down a ball carrier to the outside when a blocker stepped in his way to cut him off.

But that didn't keep Kuechly from making the play though.

''The position he was in, he should have been cut off,'' Rivera said. ''But he made a step in and the blocker came down with him and he jumped around him and accelerated to the outside and made the play. It's one of those where you just sit there and go, `Wow.'''

While the focus this summer will be on improving as a pass rusher, Rivera said Kuechly remains a special player.

''He has that kind of ability and I think a big part of it is just how smart he is as a football player,'' Rivera said.



By STEVE REED