"We just didn't play well enough," Arians said after the loss. "Our best players especially didn't play well enough."
Peterson's muffed punt was a critical gaffe, negating the Cardinals' momentum by blowing an opportunity to recover from an early 17-0 deficit.
Fitzgerald dropped two passes Sunday after flubbing just one on 268 targets over the past two years.
While those two perennial Pro Bowlers are certain to bounce back next season, it's fair to wonder how Palmer's postseason collapse will affect his confidence going forward.
Palmer hasn't been the same since suffering an injury to the index finger of his throwing hand, posting a 56.7 completion rate, 5:7 TD-to-INT ratio and a 65.5 passer rating in the last three games compared to 64.7, 34:10 and 106.8 in his first 16 weeks of the season.
Palmer never bounced back from a disastrous two-play sequence early in the second quarter when he missed an open Andre Ellington on a simple dump-off pass and took a third-down sack, turning a field-goal opportunity into a lost fumble.
It was just as fitting that Palmer uncorked his fourth and final interception two plays later, as Cam Newton exited the blowout to "MVP" chants from the home crowd.
Kuechly and the rest of Carolina's defense deserves credit for making Palmer's life miserable, but this wasn't just a disappointing outing. It was an epic meltdown with the potential to haunt Palmer in future playoff appearances.