When dynasties start to totter, people take notice. When a dynasty that almost was begins to slip, it doesn’t get quite as much attention.

The Indianapolis Colts are far from finished this season, but if yesterday’s 27-24 home loss to the Jacksonville Jaguars is any indication, their chances of hosting the entireity of the AFC playoffs are slim. And if they don’t get home field advantage for the conference championship game, it’s probably the end of their Super Bowl hopes.

Back in 2002, when Tony Dungy arrived in Indianapolis to coach three of the league’s most potent offensive players, it seemed like the Colts were a dynasty in the making. At Tampa Bay, Dungy had a legitimate reputation as one of the best defensive strategists in the league, and many gave him at least half the credit for the Bucs’ Super Bowl-winning defense.

The knock on Dungy was said to be his lack of offensive imagination. What luck then, to inherit a quarterback like Peyton Manning, a running back like Edgerrin James, and a wide receiver like Marvin Harrison. How could an explosive passing attack, a powerful running attack, and an improved defense not take a team to the Super Bowl?

Colts fans have been asking themselves that question for the last couple of seasons. Last year, the Colts seemed to be building up an enormous head of steam for the playoffs, and Manning finally shook his tag as a postseason underachiever with two spectacular victories over Denver and Kansas City.

The Colts’ 24-14 loss to eventual champ New England in the AFC title game was a hard comedown, but the Patriots were the better team, and the combination of bad weather and playing in Foxboro made it unlikely that Indianapolis would pull off an upset. The Colts began this season assuming they would be facing the Pats again for the AFC championship and feeling they would have to play in their cozy dome in order to beat them.

After losing 27-24 to the Pats in the season opener at Foxboro, the Colts won their next four games without too much trouble. But yesterday, Indianapolis, in the words of CBS’s Dan Dierdorf, “got caught looking at the scoreboard for a game that hadn’t started yet” – meaning the 4 p.m. meeting of the only two unbeaten teams in the AFC, the Patriots and Jets.

The Colts picked the wrong team to phone it in against. The Jaguars were just 5-11 last year under new coach Jack Del Rio, but they won three of their last five games and finished the season looking good. Going into yesterday’s game, they had won four of their first six, though just by 13 points; one loss was by seven points to the Colts two weeks ago at Jacksonville, a game the Jags could have won.

The Jaguars arrived in Indianapolis with a fairly solid idea of how to win: Make effective use of 6-foot-5 quarterback Byron Leftwich, counterpunch with running back Fred Taylor, and play harder than the Colts. None of these three proved to be particularly hard, though the degree to which the Colts cooperated with the last point left their fans in stunned silence through most of the afternoon.

The Colts were stung with 12 penalties (actually, 15, with the Jags declining three). Jacksonville committed just six, and four of them came on defense, which is usually a sign of aggressiveness rather than sloppiness. A whopping 10 of the Colts’ 12 penalties came on offense, leaving Manning to confront several 1st-and-15 and 3rd-and-9 situations. Play-byplay man Dick Enberg observed that Manning didn’t appear rattled by the constant flag throwing, but “he can’t seem to get his teammates to focus on the game.”

Manning put up typically impressive stats – 27-of-39 for 368 yards with three touchdowns and no interceptions – but the rest of the team, on both offense and defense, gave a clinic on how to turn a dazzling passing performance at home into a 3-point loss.

Because of salary cap restrictions, in three seasons Dungy has never quite been able to secure the kind of talent on defense that the Colts have on offense. The Colts couldn’t afford to sign their two starting cornerbacks before the season started and haven’t adjusted; their defensive backs and safeties always seem to be bringing down the other team’s wide receivers from behind.

Yesterday, Dungy hurt his team’s chances with poor decision-making. With about four minutes left in the game and the score tied at 24, Dungy uncharacteristically decided to play it conservatively and pulled back the blitz. The puzzling decision left Indianapolis’s soft secondary exposed, and Leftwich picked the Colts apart, moving the Jags in position for a game-winning 48-yard field goal with less than a minute on the clock.

Manning never really had a chance after that: The Colts incurred two more penalties before they could get their second play off and never made it across midfield. For the day, Leftwich actually had more impressive stats than Manning – 23-of-30 for 300 yards, averaging an eye-popping 13 yards per throw – and Taylor out rushed the more celebrated James, 107 yards to 87.

Manning will be 29 next year, and there’s no reason to think he won’t have several more good years, but it isn’t likely that he’s going to be better next year than he is right now. His best receiver, Harrison, is 32 and won’t be faster when he’s 33. James is just 26 – but running backs wear out quickly in the NFL.

Both Harrison and James are free agents at the end of this season, and what it will likely cost the Colts to re-sign them is going to drain even more available funds for plugging holes in that defense. The Colts might still win it all, but they have to hope now that New England takes a couple of Sundays off, the way they themselves took yesterday off.