SPARTANBURG -- First day in pads! But before we get to all the practice observations, let's start where we usually do, with Cam Newton. It was pretty much an off day for the franchise quarterback. He rested his arm after two full days of action, and it was rookie quarterback Will Grier who took the first-team reps.

"It's all part of the plan," Rivera said. "He's doing really well. No issues."

With Newton observing, it was a big day for Grier. The third-round pick from West Virginia got to see what it's like to match wits with Luke Kuechly and Co.

"Practicing with the first team is just awesome, getting a feel for the speed of the game and seeing really how fast that is," Grier said. "They're special players and it's good for me to learn. I have a long way to go, and those reps are great reps for me against guys that are vetted in the league.

"I have so much room to grow and I'm just trying to chip away at that. It's not going to happen overnight, but I enjoy the process."

Rivera was pleased with what he saw from Grier, but he passed along part of the conversation offensive coordinator Norv Turner had with the rookie after practice.

"He really kind of predetermined a couple times and Norv was trying to get him to understand, 'Hey, just go through your progression, go through your read. If you see certain things, go the other way and take what they're giving you.'"

And now, the observations.

--A bunch of vet days: TE Greg Olsen, C Matt Paradis, OT Daryl Williams, DE/OLB Mario Addison and DE/OLB Bruce Irvin.

--Wide receiver Torrey Smith (knee) and linebacker Jermaine Carter (knee) passed their physicals and came off PUP.

--One-on-one pass rush always gets attention. And overreactions. Carolina's top two draft picks faced off and Brian Burns used a filthy inside move to leave Greg Little in the dust. Say what you want about the rep. Break it down however you like (should be noted that coaches barked at Burns to finish the play and hustle back). Just know this: the drill is slanted toward the defensive player. And it's one rep from the first padded practice of the season. It doesn't mean Burns is going to the Hall of Fame and it doesn't mean Little is a bust. OK, rant over.

--Little wasn't the only one who got beat in one-on-ones. Right tackle Taylor Moton struggled to keep his balance and get a hand on Marquis Haynes, who used a swim move to get to the spot quickly. Moton was quick to credit Haynes after practice. "Yeah, he's taken a step," Moton said. "He's making me better."

--The highlight of one-on-ones between the WRs and DBs came when Curtis Samuel lined up against Donte Jackson. Samuel went deep down the sideline and Jackson was right there with him. But the ball from Grier was perfectly placed and Samuel created just enough separation to reel it in for the score. "He got lucky," Jackson told the crowd. Jackson later got back in the win column by dislodging the ball from Samuel after he had created separation for a catch against the sideline. Definition of finishing the play.

--Little, who got a ton of work as the first-team left tackle with Williams sitting out, fared much better in the team periods. He had a couple solid reps against Burns and seemed to settle in.

--The defensive backs were making a lot of plays on the ball. Cole Luke had a really nice diving PBU on a throw to Andre Levrone. Colin Jones came across the field to deny a shot to Temarrick Hemmingway. Jackson and Ross Cockrell combined to break up a long ball to DJ Moore.

--Defensive tackles Kawann Short and Gerald McCoy have been pretty much attached at the hip. They've got instant chemistry. They're always chatting on the sideline. It's a great development for Carolina's defense. Not so great for opposing offenses.

--Noticed a bunch of guys were wearing these new patches on their arms and asked team nutritionist Jennifer Brunelli what was up. Turns out the patches are for sweat testing. It measures the ounces of fluid that the player loses in sweat. It also measures the miligrams of sodium. Thought y'all might be interested in that bit of sports science.