SPARTANBURG, S.C. – Following their first day off, the Panthers returned to rain-soaked practice fields at Wofford College on Wednesday.

It also marked the return of two players who were previously on the physically unable to perform list. Wide receiver Curtis Samuel (ankle) and defensive end Bryan Cox Jr. (ankle) passed their physicals and made their camp debuts.

Samuel, a second-round pick in 2017, was involved in all aspects of practice, but the staff was careful not to put too much on him in his first day back.

"You don't want to get ahead of yourself," head coach Ron Rivera said. "He's trying to feel his way back out there."

Rookie safety Rashaan Gaulden (thigh) and tight end Jason Vander Laan (shoulder) did not practice. Rivera said they wanted to exercise caution with both.

Now on to the observations.

- The officials made their annual visit to training camp – a visit that always provides a bit of entertainment. Cornerback Captain Munnerlyn bear-hugged and picked up an official who penalized him for pass interference (hilarious picture above). Quarterback Cam Newton helped out another official by lowering his knee-high socks to a more swag-appropriate level. On a more serious note, wide receivers coach Lance Taylor had one of the officials explain the procedure for properly lining up on or off the line of scrimmage. The same official then went on to discuss the ways of avoiding offensive pass interference penalties.

- Left tackle Matt Kalil has his hands full locking horns with defensive end Mario Addison day after day. The explosive pass rusher can make tackles look silly, as many of you saw the other day. But Kalil was on the winning end today. He thwarted Addison when they faced one another one-on-one, and later Kalil and guard Amini Silatolu executed a nice combo block against Addison and defensive tackle Kawann Short (check it out below).

- During the early portion of practice when the wideouts and running backs run against air, offensive coordinator Norv Turner wants to see precision in the route-running. Every step – one less or one too many – is important. He called Christian McCaffrey back to re-run a route out of the backfield. Turner also got on Devin Funchess for not running a deep enough dig.

- Another humorous note regarding Munnerlyn. Newton spotted Jarius Wright cutting across the field and lofted a pass jusssst over the Munnerlyn's outstretched arm for the completion. The defensive sideline let out and audible groan, as they sensed an interception was coming. "Get your short (butt) outta here!" safety Mike Adams joked after the play.

- The one-on-one reps between rookies DJ Moore and Donte Jackson continue to deliver. Jackson jammed Moore at the line and was sticking to him as they ran down the sideline. But Newton's throw was put in the perfect spot – high and to the back shoulder – allowing Moore to leap and reach for the reception with Jackson turned around.

- Jackson really started feeling it after losing that initial battle with Moore. He racked up five PBUs to be exact (he counted).

"I wouldn't say his catch got something going in me; it was just getting back here on the field," Jackson said. "I was excited because I didn't practice the day before the break. He made a great play on the ball, but from that point on I locked in a little bit."

Jackson's second rep in the one-on-one drill was a good one. He reached across wide receiver Jamaal Jones for a textbook pass breakup on a crossing pattern.

In the team period, right after Jackson broke up a pass on a comeback pattern to Funchess, Newton tossed a deep ball to Moore in the end zone, but Jackson was up to the task and got his hand on it for the breakup. "D-Jack! good timing," Rivera said.

Later, Funchess tried a double move but Jackson didn't bite, running stride for stride and knocking the ball away (he said this was his best play of the day).

It looked like Jackson was going to record his first interception late in practice as he was tracking a deep ball to Torrey Smith in the back corner of the end zone. But Newton's pass dropped right in the bucket for Smith, who maintained possession as Jackson battled him to the ground.

"Torrey made a great play, a great adjustment on the ball," Jackson conceded. "But we were out of bounds. I know so."

Video review might tell a different story, Donte.

Regardless, Jackson showed what he's capable of and had really solid day making plays on the ball.

"It's good to see young guys taking advantage of the opportunities right now," Rivera said. "He had a good practice. We're starting to see guys step up, and that's what you look for."