Sure, the Bengals' struggles this season aren't completely coach Marvin Lewis's fault, but something needs to change in Cincinnati, especially after the most recent loss to Baltimore. And it should likely come from the very top.

Maybe Marvin Lewis deserves a pass for Sunday. After all, his struggling team went on the road without stars A.J. Green and Gio Bernard, and pushed the first-place Ravens and their outstanding defense to the brink before falling 19–14.

Maybe one even could write off this entire season as a product of Cincinnati’s circumstances—injuries and disappointing play at key positions, combined with a brutal schedule (all seven teams that have beaten the Bengals are above .500).

Those arguments are understandable—fair even. But they overlook the fact that Cincinnati, one of the league’s models of consistency the past five years, has regressed so badly this season that it’s difficult to see a way forward. There must be significant changes, and the easiest spot to start would be at the top, with Lewis.

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A decision to fire Lewis will not come as easily for Cincinnati as it might for other franchises with embattled coaches. He took over in 2002, after the Bengals had spent a decade-plus as an NFL bottom-feeder, and since has orchestrated seven postseason appearances and four division titles. Lewis and owner Mike Brown have, by all accounts, a tremendous working relationship, so much so that Brown allowed Lewis to craft a succession plan that would have allowed Hue Jackson to take over after the ’17 season.

What Lewis has helped accomplish in establishing Cincinnati’s homegrown, draft-and-develop model is nothing short of impressive.

Unfortunately, it also has grown stagnant. No Bengals fan needs any reminder that Lewis is 0–7 in his playoff trips; the franchise hasn’t won in the postseason since 1990. And the risk of said draft-and-develop model is that the develop part does not happen in a timely fashion.

That’s part of the explanation for how Cincinnati wound up with Cedric Ogbuehi struggling at right tackle, Green lacking a reliable No. 2 target alongside him at receiver and progression at the cornerback spot has failed to materialize.

How much of that is on Lewis? A great deal, if not all. The exact split of personnel duties within the Bengals organization always has been kept a bit of a mystery, but Brown said two years ago he had “handed off” much of the responsibility. Lewis and director of player personnel Duke Tobin call most of the shots now.

Lewis’s imprint always has been on this roster, though, which is a clear positive when things are going well and a serious issue when the train jumps the tracks, as it has during this 3-7-1 season.

For as long as Lewis and Cincinnati have been together, it has recently taken on the look of a partnership nearing its end. The rumored succession plan made that obvious, along with the three consecutive one-year contracts Lewis has signed. The latest came this past off-season, following Cincinnati dropping an opening-round playoff game for the fifth straight year. At the time, Brown hinted that there would be no guarantees beyond 2016.

“It’s a process,” Brown told Cincinnati.com. “We seem to go through our own dance. But I commend Marvin’s achievements. He’s done remarkably well with our football team here, in recent years especially. I respect him. I like him personally. He’s going to be our coach this year. That’s in the bank. Where it goes, we’ll see how it plays out.”

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Nothing much has gone right since then. Worse yet, the Bengals’ sudden drop-off has made it easy to wonder if they missed their window with the current group of players and coaches.

Oft-criticized QB Andy Dalton, who incredibly had four passes batted down on Cincinnati’s final possession Sunday before fumbling, is more or less operating on a year-to-year basis himself—his $96 million contract can be wiped from the books for a minimal cap hit after this season, and for no financial penalty come 2019. If the Bengals press the reset button by cutting ties with Lewis, might they start over at quarterback, too?

That’s an issue for down the road, and it really should be one with which the next regime has to deal.

Lewis deserves all the credit in the world for building a steady, competitive foundation in a place that had gone years without seeing much success. He also has to take much of the heat now. If you’re not moving forward in the NFL, you’re moving backward. The Bengals clearly are headed in the wrong direction these days.