Are the good times gone?

(Photos by Reuters and Jim Davis / Globe Staff)

FOXBOROUGH -- What if this is as good as it gets? What if this euphoric chapter in Patriots history is complete? What if the karma was buried right there in the desert, alongside the historic undefeated season and the run at immortality?

Presented the chance to make a statement on the cusp of December, the Patriots got their noses pushed in late yesterday in the form of a 33-10 beating by the Pittsburgh Steelers on the phony turf at Gillette Stadium. The cold, hard rain brought a cold, hard reality. Once unbeatable in their digs on Route 1 -- old or new -- the Pats now have suffered two home defeats by 21 or more points this year, something that hasn't happened in New England since the intrepid Rod Rust (mis)led the Pats to a 1-15 finish during the calamitous fall and winter of 1990.

Fine. We all know that is nothing more than a statistical quirk. But the Pats are now 7-5 entering the final four games of this season, a mere 7-6 since the start of play on Feb. 3, and we are all being served a harsh reminder of how the other half lives in an NFL world where no one is safe.

Most of the time.

"I thought we played hard out there, I just didn't think we played well," said a succinct Bill Belichick after yesterday's game. "We didn't play well enough."

They really weren't even close.

Yes, there have been injuries, beginning with the one to the talented and fashionable GQB, the inimitable Tom Brady. Beyond that, Sammy Morris, LaMont Jordan, Laurence Maroney, Ty Warren, Adalius Thomas, Rodney Harrison, and Terrence Wheatley all have missed significant time or suffered season-ending setbacks. The fact that the Pats are even still talking about the playoffs is a borderline miracle, a testament to their football operation, their leadership, and to what they have built.

Here's the worrisome part: All this time, the clock has been ticking and nothing lasts forever. Prolonged success in the modern NFL is the exception rather than the norm, and the Patriots' dominance is bound to end sooner rather than later. By the time this season plays out, four years will have passed since the Pats won a Super Bowl, a period that generally encompasses the entire second term of George W. Bush.

Look at it this way: In the first four years Belichick effectively had Brady as his starter, the Pats won three titles. In the next four, the total will be zero. (Wanna bet?) Meanwhile, the Atlanta Falcons now look better positioned for the long term than do the Patriots, which shouldn't shock anyone given the cyclical nature of professional sports.

In the NFL, especially, success is difficult to maintain. Entering last postseason, the Pats looked like a juggernaut and the New York Giants looked like a classic case of one-and-done. Since that time, the Giants are 15-1 while the Pats are 9-6. That shocking reality is precisely why Belichick preaches the importance of playing one game at a time, something far easier to do when you are the team setting the pace, in complete control of the field.

Once that control is gone, the mind is more easily infiltrated. Baltimore needs to lose. Miami needs to lose. What's Indy's record now? The Patriots of old could focus solely on themselves because they didn't have to worry about anyone else. Now they do.

"We're not worried about Baltimore. We worry about us," Pittsburgh receiver Hines Ward said yesterday when asked about the Steelers' slim lead in the North Division and the team's potential pursuit of a first-round bye. "Everyone else has to catch up to us. We've had the hardest schedule in the league and we're 9-3."

Know why Ward can get away with that kind of thinking?

Because the Steelers probably have the best team in the AFC, the Tennessee Titans included.

Recognizing that Brady's absence is a positively enormous variable, let's acknowledge the worrisome trends here. The Patriots had a chance to win at Indianapolis last month and blew the game on a stupid penalty. Against the New York Jets, in overtime, the defense failed to get off the field on a third-and-15 at the opposing 15-yard line. Yesterday, the Pats turned the ball over five times, dropped more than a few passes and gave up 161 yards rushing while allowing five sacks.

Beyond that, the New England defense has forced a total of just six fumbles this year, tied for the lowest total in the league. They have allowed 21 touchdown passes, second-most in the NFL. The draft class of 2006 looks like a collective bust -- the Pats took Maroney first and Chad Jackson second when they might have had Green Bay's Greg Jennings in the second round -- and much of the 2007 class was swapped out in the deals that brought Randy Moss and Wes Welker to New England.

Don't misunderstand. Nobody regrets the Moss and Welker deals. Those trades gave the 2007 Pats the most prolific offense in NFL history and brought them thisclose to an undefeated season. The tradeoff was that the Pats sacrificed some youth and salary cap flexibility to get there, which only made the outcome of Super Bowl XLII all the more damning.

All of this brings us back to Brady, who is now at a crossroads in his career. As such, the Pats similarly find themselves teetering on the brink. Despite playful debates about the relative importance of each -- is the coach or the quarterback? -- we all know that the Patriots success' this millennium has been built on the marriage of masterminds. The Pats had both. Every modern NFL dynasty has been built using an identical formula -- Terry Bradshaw and Chuck Noll in Pittsburgh, Joe Montana and Bill Walsh in San Francisco, Troy Aikman and Jimmy Johnson in Dallas -- and the Patriots clearly are no different.

But now? Let's be honest. We don't know if Brady will be the same player again, be it because of the knee or anything else. He is getting older, too. He has other things in his life that seem as important to him (or more so) than football. Meanwhile, the Patriots have at least temporarily slipped into the middle class like Henry Hill, the onetime large-living mobster of "Goodfellas" who entered the witness protection program, sacrificing his essence to ensure his existence.

For a time, Hill had the best of everything.

In the end, he had to live his life like an ordinary schnook.