On Monday that meant shuffling the depth chart around.
''It's just two guys that earned an opportunity more than anything else,'' Rivera said. ''And that is what I'm going to do - give guys opportunities. Nobody has been anointed the starter or anything like that.''
Rivera said it wasn't meant to be a message to Alexander.
Kony Early continued to work at the left end spot with regular starter Charles Johnson still bothered by a calf injury. Johnson, who missed the preseason opener at Buffalo, tried to practice Monday but experienced some soreness and pulled himself out.
Rivera said he's not concerned about the position overall - one the team didn't address in free agency following Hardy's departure to Dallas - saying it's still early in the preseason. However, he'd made it clear he'd like someone to step up and win the right end spot rather than handle playing time on a ''by committee'' basis.
''If one guy steps up and becomes the watermark, everybody competes to get more playing time,'' Rivera said. ''That's what I'm hoping for as far as somebody stepping up at that position.''
The problem is two-and-a-half weeks into training camp nobody has earned that job.
Carolina's first- and second-team defense failed to produce much pressure on the quarterback in a 25-24 preseason win over the Bills on Friday night. It didn't help that starting defensive tackles Star Lotulelei and Kawann Short didn't play due to injuries.
The only real pressure came from Cox, but that was late in the game against Buffalo's third team.
Now Rivera wants to see if Cox and Miley can produce with the first team.
Alexander, who missed 14 games last year due to consecutive substance abuse suspensions, and Ealy appeared to be the top two contenders to win Hardy's old spot.
But Monday's moves at practice leave the position more open than ever before.
Rivera said the decision to give the younger players more playing time isn't an indictment on how Alexander played, but more about wanting to see what the rookies can do against first-team offensive linemen. Cox struggled in his first day going against Panthers starting left tackle Michael Oher, who threw him to the ground twice.
''Who knows, maybe one of these young guys might be the answer,'' Rivera said. ''We're gonna find out. We're going to give guys opportunities that earned it.''
Mario Addison is also in the mix at defensive end, but considered a pass rush specialist only, not an every down player.
Before practice, Ealy and Alexander acknowledged the defensive ends need to start stepping up.
''With this being our first game back, you expect stuff like that,'' Ealy said. ''I know coach had a different mindset, especially for the defense.''
Alexander said he was disappointed in the way he played, but remains confident things will get better.
''We didn't get as much sack production as we wanted but that is why you got three more games to work your way up,'' Alexander said.
Cox is trying to making the most of a second chance in the league. He earned a shot with the Panthers after working out at the recently-formed NFL veteran scouting combine.
He had two tackles and a sack against Buffalo late in the game to help seal the win.
''Before going out, my D-line coach said it's going to be on us,'' Cox said. ''It starts with us to make something happen. I kind of just went out there and took it upon myself to make a play. As a defense, we got the `W' and finished off strong. It worked out.''
NOTES: The Panthers re-singed kicker Matt Wile and reached an injury settlement with tight end Jamie Childers. ... Wide receiver Kelvin Benjamin was limited in practice after taking a hit to the middle of his back against the Bills. ... Short returned to practice Monday.
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