CHARLOTTE — In the moments after straining his hamstring last Sunday against the Cardinals, Panthers safety Jeremy Chinn headed over to the stationary bike on the sidelines to try to keep himself warm.

He was hoping the feeling he feared would pass. It didn't.

Chinn was placed on injured reserve Wednesday, which rules him out for at least the next four weeks.

"I knew," Chinn said Thursday. "I didn't know how bad it was. But I was doing whatever I could to try to get back on the field. But it was telling me no the whole time. So just listened to it."

Chinn described the injury as a "really bad strain," which he said happened when he "overextended" trying to make a tackle. But he seemed confident that his absence wouldn't extend too far past the four weeks he's required to miss.

"My goal is to be ready to play as soon as my IR is up," he said. "That's what I'm preparing for. I'll be prepared to go as soon as I'm ready.

"It is frustrating, but trying to get past the frustrating part and get back out there."

Chinn has been durable in his career, missing only two other games, one in each of his first two seasons.

The Panthers signed veteran Juston Burris off the practice squad to fill his roster spot, giving them an experienced presence in the back of the defense. They also have Myles Hartsfield and Sean Chandler they can use as they mix and match the secondary.

— As part of their recent issues on offense, the Panthers are last in the league in time of possession (averaging 24:18 per game).

That shows up on defense when they have to play so many more snaps, and the 16 fourth-quarter points the Cardinals scored were part of a trend. The Panthers have allowed 42 points in the fourth this year, more than double what they have in any other quarter (6 in the first, 20 in the second, 17 in the third).

But veteran defensive coordinator Phil Snow wasn't using that as an excuse.

"You know, we don't even talk about that, right?" Snow said Thursday. "We've got to play for 60 minutes, and really our goal is that they have fewer points than we have.

"That's the goal every week, and it doesn't matter if you're on the field 50 plays or 80 plays, that's the goal. So that's what we talk about."

Snow said he didn't think having to defend more plays made him change the way he called games, and he likes the way they've been able to rotate players. They use a pretty steady rotation on the defensive line, and the number of different coverages they play allows him to keep multiple defensive backs on the field at different times.

"I've been really happy with our rotation of our players," he said. "But when I call the game, it depends on down and distance and what they do out of that group and all that. I'm not really looking into the time of possession when I call it."

— Quarterback Baker Mayfield's role in the recent offensive issues has been well-documented, but offensive coordinator Ben McAdoo said Thursday that they've seen things in practice that suggest he's capable.

It's traditional that quarterbacks get outsized shares of both credit and blame, and with the Panthers last in the league in total offense and third-down conversions, Mayfield is certainly getting plenty at the moment.

"I think it's easy to sit back and point fingers at Baker and say Baker's doing this and Baker's doing that, it's the reason we're not successful," McAdoo began. "I think Baker doesn't get enough credit for what he's been able to do. He's come in here in training camp, half the reps with the ones to learn a new system that he's never been involved in.

"He's getting better in practice, and we just need to keep working and carry that over to games. The guy's a fighter. I believe in him. And I'm looking forward to it to start clicking."

Mayfield's numbers are well off his career averages (even last year when he was injured in Cleveland), and McAdoo pointed to some specific things he's seen on the practice field when asked what hasn't translated.

"I don't know that it all hasn't translated," he said. "I just think he sees the field really well, he processes information quickly, and he does a tremendous job being decisive. He's a decisive decision-maker; he has a feel for where he needs to go with the football. He's not a guy that needs a ton of reps to get some things done; he's been really clean."