CHARLOTTE—The message, in Derrick Brown's mind, was simple.

"You got to go back to work. We got our ass whooped today," Brown said, shaking his head after the Panthers' 40-9 loss the Bills. I mean, hats off to them. They whooped our ass. So got to go back to work. We sat in this same position four weeks ago."

The position four weeks ago was coming off a 42-13 loss to the Patriots. The Panthers bounced back from that by railing off three straight wins, which means they're still 4-4.

"We sat here, we had these same questions four weeks ago, like I said, right?" preached Brown. "And you know for us to be able to snap back from that, I mean, coach breaks it up into the quarters, the season in the four quarters, and we just finished our second four games."

Dave Canales always preaches finish, particularly in the fourth quarter. In relation to the season, to Brown's point, the Panthers have just finished their second quarter, and everything is tied. So, what happens next?

"I mean, back to the drawing board," said Brown. "We know what we do well. We know what we do good. Now we just got to go out and execute it at a high level once again."

Doing so will require first addressing what went wrong on Sunday against the Bills. The game was billed as a matchup between two of the best rushing offenses in the league. In the end, only one made their mark.

James Cook III rushed 18 times for 216 yards and two touchdowns in Sunday's game, breaking a Panthers franchise record for rushing yards allowed by an individual. It was Carolina's first home loss of the season, and the worst rushing defense performance of the year thus far.

Asked what went wrong, Jaycee Horn answered quickly, "Everything." Considering the Bills put up 410 yards and 40 points, with 17 points off turnovers and two Buffalo drives starting deep in Panthers territory because of said turnovers, "everything" about sums it up. It was the 245 collective rushing yards, with the aforementioned 216 from Cook, that really told the story on defense, though.

"They had over 200 yards rushing," continued Horn. "Whenever that happens, it's hard to stop—the whole playbook opens, so it's hard to stop anything. And just playing complementary football, we didn't do a good job of that today. We couldn't stop anything, and the offense couldn't get anything going, and that's a recipe for disaster."

Coming into the game, the Panthers' defense had not allowed a single rush of more than 6 yards in the last three games. Cook took care of that on his first touch of the day, running hard around the left end for a gain of 12 yards.

Cook worked the edges that way all day, actually, using a toss crack that allowed him to do so.

"Just explosive play," Canales said of the difference on defense. Cook had seven runs that were considered explosive (10-plus yards), including both of his touchdowns. "I thought James Cook did an excellent job of being patient. And just really slow-playing (it). They did a great job up front, staying on their combinations, and didn't feel like we could collapse the backside of some of these runs.

"There were some cutbacks that got out got out on us, and the toss cracks really were effective for them today. So, stuff we got to look at, and you know, this is a copycat league, and teams are going to see that and try to attack us with those things. So we got to go back to the drawing board and make sure we're fitting all those up correctly."

Echoed Horn, "Team's been hitting us with perimeter runs, and they've been successful, so got to find a way to stop it."

The Buffalo running back, who came into Sunday fourth in the league in rushing with 537 yards (just behind Rico Dowdle), posted a career-best rushing day with those 216 yards, and was 5 yards shy of his career-best total from scrimmage.

"Simply put, everything," responded Bobby Brown III as to where the defense failed to contain Cook. "We didn't do what we needed to do game plan-wise, plan-wise, effort-wise; we just didn't play better football."

The Panthers' locker room was frustrated following the loss, disappointed in the performance just as much, if not more so, than the loss. But there was also little resignation, and no discernible sense of panic. Having that bounce back four weeks ago raised the bar for where this team feels they are and, more importantly, for what they are capable of.

"We were just able to come in, calm down and execute," said Derrick Brown of the blueprint to follow. "Nobody gave us a chance then, so I mean, you know, we're back to square one, like I've been saying. Shit, we'll be back here, you know what I'm saying, so I mean it's one of those things where this is how it happened, so we got humbled today.

"Humility is definitely a measuring stick for us today, so we'll take this one on the chin and get back to it."