It's tough to win 13 games in an NFL season. 

How tough, exactly? Well, the other three teams in the AFC East - Bills, Dolphins, Jets, in case you needed a refresher - have won 13 or more games a total of four times in a combined 150 seasons of professional football.

The Patriots have won 13 or more games five times in the last nine seasons.  

So I'll enter this with some sense of perspective: The 2011 Patriots have had, by almost any measure, a terrific year. There isn't a team in the NFL - that includes the Patriots - that wouldn't sign for 13 wins before the start of any season. Sure, we all know about the defense - and those concerns are very real - but Tom Brady throwing for over 5,000 yards plus the league's leading receiver and the most productive tight end combination in NFL history (by over 40 catches)? Pretty good bang for the ol' buck.

Put it another way: Browns fans would happily trade years off their lives for what we just watched over the last four months. 

But if this team loses to Tim Tebow and the Broncos at Gillette Stadium on Saturday night it will be the worst loss of the Bill Belichick/Tom Brady era and will officially put the 2011 season in the "totally and forever lost" category. No one would remember 5,235 yards passing, or Gronkowkski breaking records or Wes Welker's 99-yard TD or Vince Wilfork's interceptions or Andre Carter's four sacks against the Jets. It would all be wiped out, replaced by a buffet of Tebowing at Foxboro. 

Let's not confuse "worst" with "most painful." The birth of 18-1 will always be the champion nut-kicker in New England sports history. And the AFC title loss to the Colts was an absolute killer, an almost certain Super Bowl choked away to Peyton Manning and Saint Dungy.

But those were losses to great football teams, or at the worst very, very good football teams. You know how I know? Both won Super Bowls (and there's your Phil Simms, Captain Obvious entry of the week). As for the other three playoff losses of the Belichick/Brady years, two came to teams with impressive pedigrees (the 2010 Jets were flawed, yup, but did win 11 regular-season games and were AFC Title Game reps for the second straight year, and the 2009 Ravens made the playoffs the year before and have done so the two years after) and the third was ultimately a statement on a New England team that was seriously deficient in skill players (and tapped out to Jake Plummer and the Broncos with very little fight, save for the defining 10 seconds of Ben Watson's career). 

The 2011 Denver Broncos are not a great football team (wow, maybe I could be the lead analyst for CBS after all). They went 8-8 in a truly putrid division, lost their final three games of the regular season and were pushed into the playoffs by that always powerful combination of Carson Palmer's mediocrity and Norv Turner's ineptitude.

But let's be fair: They went out on Sunday and beat a Steelers team that handled the Patriots on October 30 (back when there used to be snow on the ground in New England). Was Broncos 29, Steelers 23 a classic? Nope, but it was sensational theatre. Comebacks, big plays, guys playing hurt, shaky efforts by the officials, the first overtime under the new rules, Phil Simms gamely attempting to analyze the entire contest while blindfolded, a stunning finale, all that stuff. 

And Tim Tebow out-played Ben Roethlisberger, a First Ballot Hall of Famer (and First-Ballot Hall of Fame creep, as we briefly pause to remember that were if not for the boobitude of the Milledgeville police department Big Ben would likely be about 12 months into a prison sentence) without any debate. The game started with many if not most expecting to see Brady Quinn replace an ineffective Tebow and ended with John Fox, John Elway hugging the Kind of Chosen One and 75,000 fans (was that crowd noise at an NFL game? Wow, must've closed the wine and cheese store at halftime) in, for at least that moment, complete belief.

Great. Swell. Good for Tebow, Fox, Elway, Denver and karma (again, comes back to Milledgeville). But there's a reason why we all thought Brady Quinn - he of the zero playoff appearances, career 66.8 passer rating and now a Ph.D in clipboard holding - was going to get some snaps on Sunday. 

As a person, Tim Tebow might just be everything we're told he is. Maybe he's genuinely solely worried about serving Jesus Christ. I have no idea who Tim Tebow is because I'm not his friend or a member of his family, but he's done nothing to suggest that he's anything but a well-meaning and extraordinarily caring human being (the guy gave all his $2.5 million signing bonus to charity, for just one example).

But as a quarterback, there are still red flags all over the place. Yes, he made plays on Sunday against the NFL's top ranked defense. It was, however, a defense missing its entire starting line and safety Ryan Clark (a monster loss - the secondary looked clueless without him). And Tebow still completed less than 50 percent of his passes (10-of-21, and there was plenty of separation from the receivers) and still often looked to be almost incomprehensibly inaccurate for a starting NFL quarterback (his 46.5 completion percentage in the regular season was the lowest by a qualifying QB since Akili Smith's 44.2 in 2000).

If you aren't already sick of all things Tim Tebow, you'll be vomiting by Wednesday or Thursday at the latest. He knows how to win, there's magic around him, his teammates will follow him into fire, you know the drill. But the numbers tell a consistent story with Tebow: The guy simply isn't good enough to be an NFL quarterback and he won't last if he doesn't figure it out.

An 8-8 team (9-8, sorry) with the most inaccurate quarterback of this century cannot come into Foxboro and beat Tom Brady and Bill Belichick, right? A team that the Patriots beat 41-23 (including a 27-0 run) in Denver on December 18, a game that saw the Patriots put up 451 yards of offense, sack Tebow four times and force a pair of fumbles from the QB, cannot walk into Gillette and end this season, can they? 

Look, we all know that this Patriots defense is whatever it is - some call it opportunistic, some call it the worst in football, let's split the difference for now - and the Super Bowl is far from promised to this team. Unlike last year, which saw the Patriots roll into the postseason with recent blowout wins over the Steelers, Bears, Jets (jumped out to a combined lead of 63-0 in those games) and the title of clear-cut favorite, there is correctly plenty of doubt. A hard-fought loss to the Ravens in the AFC title game would not be viewed as a disgrace (by all of us not named Borges, I suppose), or even a 41-28 loss to the Saints or Packers in Indianapolis. There will never moral victories, or lessons in defeat, or wait 'till next years with Belichick and Brady, but this isn't a Super Bowl or bust team. 

But a third straight home playoff loss, this time to Tim Tebow and the Broncos less than a month after blowing them out on the road?

Won't happen, it says here. Let's call it 31-17, Patriots. But if the (sort of) unthinkable happens, and Belichick and Brady go down to Tebow and the 8-8 AFC West champions? 

A disaster.