NEW YORK >> Come one, come all to MetLife Stadium on Sunday. The C students. The 12-handicap golfers. The middle managers.

The occasion? A daylong celebration of the ordinary and the middling — warm coffee, half-cooked hot dogs and watered-down beer will be served — with the marquee event beginning at 1 p.m. That is when the game most emblematic of this NFL season will kick off.

The New York Jets versus the New York Giants in the Mediocrity Bowl. In this parody of parity, the winner enhances its postseason standing while the loser suffers the indignity of still remaining relevant in the playoff chase.

Only seven of the league’s 32 teams are 7-4 or better, the fewest at this stage of the season since the NFL expanded to 32 in 2002. The pileup of teams — 13 in all — at 6-5 (the Jets, losers of four of their last six, among them) or at 5-6 (hello, Giants, also losers of four of six) is the most over the first 12 weeks of a season.

“If you’re a shill, then it’s parity,” Dan Fouts, a Hall of Fame quarterback and an analyst for CBS Sports, said in an interview. “If you’re a pessimist, then it’s mediocrity.”

Seven other squads entered Week 13 at 4-7, including the Philadelphia Eagles, who have been toasted for 10 touchdown passes over the last two weeks but, because of the ineptitude engulfing the NFC East, sit just a game behind the division leaders.

Those powerhouses would be the Washington Redskins, who have allowed 26 more points than they have scored, and the Giants, whose roster of defeats features a cornucopia of bungled clock management and fourth-quarter collapses. The lone redeeming quality of their games is Odell Beckham Jr.’s weekly installment of “How Did He Catch That?”

For a league that created a RedZone channel, there are a lot of teams that struggle to get there — and to figure out how to breach the goal line if they do.

Vince Stone, a football fan from Cleveland, Tennessee, supports two of those low-scoring teams, the Tennessee Titans (2-9) and the Dallas Cowboys (3-8), who this season are struggling for mediocrity, a subject near and dear to his heart. Stone, it could be said, wrote the book on being average.

Exasperated by a self-help industry he felt was milking the public of millions of dollars, Stone wrote “Embracing Your Inner Mediocrity: Making Peace With Reality,” a satire intended to soothe a populace conditioned to perceive second place as just the loser to first place.

“I think the word mediocrity gets a very, very bad rap,” Stone, a library director in north Georgia, said over the phone. “It’s just another word for average. It means you’re average, and most of the employees out there are average.”

For some professionals, like airline pilots and the surgeon who inserted the stent after Stone had a heart attack six months ago, being average is impermissible, or at least not recommended. In the NFL, where in Week 13 all 32 teams remain mathematically alive, it is rewarded.

“How can you be 2-9 like Cleveland and not be eliminated from the playoffs?” Mark Dominik, an ESPN analyst who spent five years as the Tampa Bay Buccaneers’ general manager, said before answering his question.

Because five games remain, he pointed out, and the Browns trail sixth-seeded Houston by four. The odds of Cleveland’s snaring a berth are about as good as having a game-winning field-goal attempt blocked and returned for a touchdown as time expires (oh, wait), but they do exist, and that is what the NFL wants.

The games still are often compelling, and if anything, they are more competitive: Teams have trailed by 8 or fewer points in the fourth quarter in 69.5 percent of the games (123 of 177), tied for third most in league history through Week 12.

But fans and analysts have noticed a decline in the overall quality, propagated by a preponderance of penalties and poor tackling, and what Fouts and Dominik called a transitional period at quarterback. As some of the greats approach the ends of their careers, the next wave has yet to assert itself.

Instability at the position reigns for about one-third of the league, while other teams, from Tampa Bay to Tennessee to Washington, are enduring the ebb and flow that comes with starting a young quarterback.

“I think that some of these unwatchable games, you just look at that position and you go, ‘Well, that’s why,’” Fouts said.

The pressure to unearth a franchise quarterback is immense, so when a team determines it has one, it often tries locking him up. But if that evaluation flops — see San Francisco (Colin Kaepernick), and perhaps Detroit (Matthew Stafford) and Miami (Ryan Tannehill) — the impact can ripple throughout the team.

“You’re paying quarterbacks all this money, so you have to play these 22-, 23-, 24-year-olds elsewhere because they’re the only ones you can afford,” said former NFL center Shaun O’Hara, now an analyst for NFL Network. “You’re playing these younger guys not because you want to but because economically you have to. They’re the cheaper player.”

And herein lies what O’Hara and Dominik perceive as the bigger, leaguewide problem. More and more important roles are filled by these younger players, who need time to adjust to the NFL but have spent their entire careers in a league governed by a collective bargaining agreement, reached before the 2011 season, that, to protect players from concussions, scaled back the intensity and frequency of practices.

The new agreement lopped five weeks from the offseason program, outlawed two-a-day sessions in training camp and tolerated only nominal physical contact. With tackling and blocking difficult to simulate when players are not in pads or at full speed, they say, the repercussions have reverberated throughout offensive lines and defenses around the league. Most of the games in September, O’Hara said, were “unwatchable.”

“It looks like they haven’t even practiced full speed,” O’Hara said. “I don’t think players are really starting to perform at their best until October. Even the good teams who start 1-3, they just played so sloppy that now they’re fighting and clawing to get back in.”

Perhaps O’Hara was alluding to Kansas City and Houston, which over the last six weeks have surged to seize wild-card spots in the AFC. But with five games left, their spots are hardly secure. They are competing with Indianapolis and the Jets and Pittsburgh and Oakland and Buffalo, and don’t rule out Baltimore, and maybe Jacksonville, and what about San Diego and Miami, and how about those Titans and Browns?

“The season is going to end before we know it,” Stone said. “Regardless of the mediocrity we’ve suffered through, we’re really going to miss it come January.”

© 2015 The New York Times Company