In the final game of the 1999 season, already sporting a 13-2 record and locked into the No. 2 seed in the AFC playoff bracket, the Indianapolis Colts traveled to Buffalo, and got walloped, 31-6, by a Bills team that had claimed a wild-card berth.
Two weeks later, following that beating and then a subsequent first-round bye, the Colts were dispatched from the divisional round of the playoffs, losing to Tennessee in the RCA Dome. The seeds of that 19-16 playoff defeat, Colts quarterback Peyton Manning still believes five years after the fact, were sown in Buffalo, in a regular-season finale in which Indianapolis barely showed up.
Which explains, to some degree, why Manning and some other Indianapolis veterans who recall their 1999 collapse would rather exit this Sunday's regular-season finale against the Denver Broncos with a victory instead of a vacation.
"Looking back on that '99 game," recalled Manning, "we lost our momentum that day in Buffalo, and we never regained it over the next two weeks in time for the playoffs. There is just something to be said about going into the playoffs on a roll. You want to feel good about yourself."
Conventional wisdom holds, of course, that the slate gets wiped clean for the playoffs and that all dozen postseason franchises begin the pursuit of a Super Bowl title from scratch. Technically that is true. In application and in history, however, that isn't necessarily the case. Since the league instituted the 12-team playoff format in 1990, teams that advanced to the playoffs on regular-season winning streaks of three or more games won more than 70 percent of their postseason openers.
So there is definitely something to be said for momentum. And that clearly makes teams such as Buffalo, Carolina and New Orleans dangerous first-round playoff foes. None of the three might even qualify for the 2004 playoff pool, since each needs a win on Sunday, coupled with some outside assistance. Teams that have already received their postseason invitations, though, don't want to see the Bills, Saints or Panthers on their opening-round dance cards, that's for sure.
The Bills, winners of nine of their last 11 games and six in a row, could become the first team since the 1992 San Diego Chargers to open a season 0-4 and still reach the playoffs. Last year's NFC champions, the Panthers are trying to come all the way back from a 1-7 start to see if they can defend their crown. And the perennially underachieving Saints, a team with as much offensive talent as any in the league, have cobbled together a three-game winning streak that apparently has saved coach Jim Haslett's job.
There are franchises that have already secured playoff spots and which have even more momentum -- Pittsburgh has won a franchise-record 13 straight games, Indianapolis is on an eight-game roll, New England has won seven of eight and Philadelphia six of seven -- but none of those teams possess any more confidence than the three clubs desperately fighting just to get into the playoff door. And the aforementioned four clubs with playoff spots already secured also are set in seeding and are theoretically playing for nothing this weekend.
Conversely, the Saints, Panthers and Bills are like runaway snowballs. By Sunday night, truth is, they might be melted. On the flip side, there is a chance at least two of them will have turned into a playoff avalanche, capable of exacting postseason damage.
Confidence born of having been through a crucible, from demonstrating mettle in adverse conditions, is a treasured commodity. In the game of "Survivor" that is the NFL playoffs, where one misstep sends a team home, the significance of such confidence and perseverance should not be underestimated.
For the most part, the playoffs generally hold true to form, and not since 1996 has a fifth- or sixth-seeded team advanced to the conference championship contest. But there seems to be a suspicion this season, particularly in the abysmally diluted NFC, that one of the stretch-run teams could actually make some noise.
"You look at those teams, especially Buffalo and Carolina with the way they're playing, and you don't want to meet them in (a first-round) game," said one AFC coach whose team will not be in the playoffs. "I mean, those teams are already kind of playoff-tested, because the last month has been one big elimination round for them. So they've already got a playoff edge to them, you know? They've been in survival mode for a while now."
It is, indeed, that survival mode, and the momentum it has created that makes clubs that have already qualified for the postseason more wary than usual of those still scraping to earn a playoff spot. One of the principle laws of physics is that bodies in motion will remain in motion until acted on by an external force. If the Bills, Panthers or Saints continue to roll forward this weekend, and squeeze into the playoffs, it could be difficult to knock any of them off course.
League wide, there are coaches and teams facing the conundrum this week of whether to play their starters and for how long. There is no such agonizing decision for Haslett, or Buffalo coach Mike Mularkey or John Fox of the Panthers. And that is another element of why no one wants to play those teams in the postseason.
"We've found ourselves as a team," said Buffalo weak-side linebacker Takeo Spikes, one of the Bills' emotional leaders. "We know what we're about now. It's not like, if we get the wild-card spot, we have to flip the 'playoff switch' and turn up our intensity. I mean, we're there already, you know?"
Len Pasquarelli is a senior writer for ESPN.com.