Is the Manning Era as we know it already over?

A forgetful week by Peyton and Eli Manning serves as a stark reminder that the Manning Era may already be over.

Between Eli’s costly and inexplicable late-game brain cramp in Dallas and Peyton’s underwhelming display of weak-armed passing in Denver, it has been a rough week indeed for the Brothers Manning. And dare I say it, the worst may still be ahead.

If there is a tougher assignment for an NFL quarterback than the one Peyton Manning has drawn this week, I don’t know what it would be: A short-week road trip for a Thursday night game in the hostile environs of Kansas City’s home opener at Arrowhead Stadium, facing a Chiefs team that boasts Justin Houston and the league’s most disruptive and dangerous pass rush.

That’s a recipe for potential carnage. Especially for a 39-year-old quarterback who surprisingly ended up on the Broncos’ injury report this week with some sort of nebulous back ailment that required treatment. Maybe even the mere thought of trying to elude Houston and the rest of the Chiefs’ relentless pass rush—after getting knocked around pretty good by Baltimore’s defense on Sunday—gave Manning some preemptive aches and pains and convinced him to sleep in a hot tub.

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Remember, it was less than a year ago that we saw none other than Tom Brady look and play like an old man in that same frenzied Kansas City prime-time setting, with No. 12 flummoxed so thoroughly in that 41–14 Chiefs win that Bill Belichick was actually asked if he was considering a quarterback competition in New England. Of course that story had a happy ending for the Patriots last season, and who knows, this one may too in Denver’s case.

But I seriously doubt it. If Manning struggles mightily to throw the ball and put points on the board against the Chiefs—a team he has beaten a record-tying eight times in a row—get ready, because Friday morning is going to bring a whole new wave of the “Is this the end of Peyton?’’ debate that has been posited in some fashion since his 2011 neck injury. Only this time it may well be warranted.

Manning is a proud and resilient athlete who has proven before that reports of his demise were greatly exaggerated, but I don’t like his chances to add another chapter to that particular book in 2015. He can claim his halting transition to the new offense that head coach Gary Kubiak has installed in Denver is a situation where growing pains are involved, and that may well be true. But the eyes don’t lie. He arm looks limited. His reactions seem slowed. And his recent results aren’t in the same league with the player who ranks as the most prolific passer in league history. His game looks diminished.

Going without a touchdown pass against the Ravens in Denver’s 19–13 season-opening win raised eyebrows, but in reality it’s becoming more of the norm for the quarterback who has thrown a record 530 such scoring tosses. In three of his past five regular season games, Manning has been blanked in terms of touchdowns passes, after throwing at least one in the 51 regular-season games before that. They say that anything that happens three times qualifies as a trend.

So a current check of the NFL’s First Family of quarterbacks shows Peyton in Denver looking as if his game is suffering a precipitous and perhaps irrevocable decline, and Eli in New York suffering the most galling mental meltdown of his 12-year NFL career, effectively costing the Giants a season-opening upset of the Cowboys with a dose of horrendous clock management more befitting a rookie QB. Definitely not an elite one.

Not to get too far out ahead of this story, but suddenly doesn’t that remarkable eight-season period from 2006 to 2013, when the Manning brothers played in five of eight Super Bowls, winning three rings, seem longer ago all the time? Like an era that has possibly passed without us quite realizing it?

Yes, Eli Manning was just rewarded with a fat new franchise-quarterback worthy contract extension from the Giants, and likely has at least another five seasons left in him. Though not currently foreseeable, perhaps there will even be a late-career championship to come.

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But those two Super Bowl rings aside, the reality is Eli now leads a mediocre Giants team that is struggling for relevancy, having missed the playoffs three years in a row (Peyton has never endured a streak of even two seasons) and started 2015 with one of the worst possible losses imaginable. New York is a humbling 22–27 since winning that second Super Bowl in February 2012, and Manning’s somewhat inconsistent performance over those 49 games relegates him to only the second tier of the game’s quarterback hierarchy—and that’s arguably being charitable.

There was plenty of blame to go around for the Giants’ fourth-quarter debacle in Dallas. But any reasonable examination of the multiple examples of faulty decision-making has to lay most of it at the feet of Manning, who first lost track of the Cowboys’ timeout situation, compounded that mistake by twice bizarrely instructing running back Rashad Jennings not to score, and then made the mind-boggling call to throw his third-down pass out of the back of the end zone, stopping the clock as a gift to Jason Garrett’s grateful team.

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I’m afraid this one is going to leave a lasting mark on Eli’s reputation and on the record of a Giants’ team that did everything else it had to do to orchestrate a tone-setting Week 1 road upset of the defending NFC East champions. Whether or not New York recovers from the huge opportunity it wasted against the Cowboys remains to be seen. Both the Giants and Manning must prepare this week for a visit from a noticeably improved Atlanta team that just knocked off the division rival Eagles at home on Monday night.

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Is there a rebound ahead for both brothers this week? The Mannings are known for comebacks, and they’ve made the doubters look like idiots many times before. By late Thursday night, if Peyton looks like the Peyton of old against the Chiefs, rather than just old Peyton, it could happen again.

But alas, the odds are far greater it doesn’t, and I’m coming around to the realization that we’ve probably seen the best both Peyton and Eli have to give. It feels like time to start wrapping our heads around that idea. The NFL’s memorable and multi-decade Manning era isn’t over, but it’s on the wane. The days of sustained dominance are likely gone, and now it’s about appreciating whatever moments of magic remain. However few.