PITTSBURGH - The Pittsburgh Steelers are accomplishing as an underdog what they couldn’t do so many times as a favorite under coach Bill Cowher, winning on the road in January after countless postseason failures at home.

The Steelers are going to a sixth AFC championship game in 14 seasons under Cowher, one of the most successful NFL coaches in history who hasn’t won a Super Bowl. Only they’ve never gotten there the way they did in stunning the Colts 21-18 Sunday in a divisional playoff game — barely a month after it seemed the Colts might not lose all season and the Steelers might not make the playoffs.

It all ended improbably on a 46-yard field goal miss by Mike Vanderjagt.

“The range of our emotions there were all over the place,” said Jerome Bettis, whose fumble at the Colts 2 in the final 90 seconds almost turned the game for Indianapolis.

Now, the Steelers, albeit with a huge sigh of relief, are headed to Denver for their first road AFC championship game since a January 1986 loss in Miami.

And they’re going there with confidence, momentum and the belief that having to win three games on the road in three weeks isn’t a big enough obstacle to keep them out of the Super Bowl. Until this season, one sixth-seeded team — the 1999 Dolphins — had won a game in the AFC playoffs. Now, the Steelers have done so twice in eight days.

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“Everybody was ready to put Denver and Indianapolis in the championship game,” wide receiver Hines Ward said. “We’re the same team that went 15-1 last year and made it to the championship game. We’re coming from a different perspective now, being on the road playing two tough road games. We all believed in one another, even if no one else did.”

The coach believes, too.

Cowher showed that by gambling twice successfully on fourth-and-short situations at midfield in the second half. A year ago, he played it safe in the AFC title game against New England by going for a short field goal instead of a touchdown that might have gotten them back into a game they ended up losing 41-27.

“We’re playing to win,” Bettis said. “We’re not playing not to lose.”

And they’re going to Denver despite a seemingly blown call that got the Colts back into a game the Steelers owned since the opening moment. Troy Polamalu thought he had cleanly intercepted a pass from Manning early in the fourth quarter, but the call was reversed and Indianapolis went on to score its second TD in four minutes and make it 21-18.

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“That play right there they tried to take the game away from us,” said linebacker Joey Porter, indicting the NFL and the game officials. “Somebody has to say something. That isn’t right.”

In the same way it doesn’t seem right that these Steelers are in the AFC title game.

“It doesn’t matter — they counted us out about six weeks ago,” Porter said. “Don’t change now. Everybody was against us, so let’s keep it that way, it keeps a chip on our shoulder. It makes us play like we know how.”

After an excellent week of practice, the Steelers were convinced they had the defensive game plan to control Peyton Manning. Some of the plan was swiped liberally from the blitz-heavy Chargers’ scheme that so controlled Manning in the loss that ended Indianapolis’ chance for a 16-0 season.

Their offensive plan was the reverse of most Steelers playoffs teams under Cowher — come out throwing, seize the lead, then sit on the lead with Willie Parker and Jerome Bettis, rather than setting up the pass with the run.

“They really did have a lot of confidence, which was great,” said team chairman Dan Rooney, who has seen every playoff game in Steelers history and sensed last week this game might be special.

That was almost the problem — the Steelers may have been too confident.

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Up 21-3 and the upset of the season all but theirs, they became too run-predictable and the Colts surged back in the fourth quarter during what almost was one of the greatest playoff comebacks in NFL history.

Almost.

This is the second time in as many seasons the Steelers have escaped their divisional playoff game because of a kicker’s gaffe. Last year, the Jets’ Doug Brien twice had a chance to kick a game-winning field goal in the final 2:02 of the fourth quarter, only to miss both. The Steelers went on to win in overtime.

“That was one of the craziest games I’ve ever been in,” a visibly relieved Porter said. “I feel good the ball actually bounced our way in the playoffs one time.”

Controversial calls in Steelers-Colts What's the catch? On first-and-10 from the Indianapolis 44 with 5:33 left, Colts quarterback Peyton Manning threw to tight end Bryan Fletcher near midfield. Troy Polamalu stepped in front, caught the ball, tumbled with it in his hands and lost it when got up to run. The Colts challenged the play, which was reversed by referee Pete Morelli even though it appeared Polamalu had possession. Manning then drove the Colts for a touchdown and a 2-point conversion to make it 21-18. Morelli said: “I had the defender catching the ball. Before he got up, he hit it with his leg with his other leg still on the ground. Therefore, he did not complete the catch. And then he lost the ball. It came out, and so we made the play an incomplete pass.” Might as well jump On fourth-and-inches from the Pittsburgh 48, two Colts defensive lineman ran across the line of scrimmage, pointing at the Steelers as if one of the linemen moved. The officials stopped the game, but called no penalty. Replays appeared to show Alan Faneca barely flinched. But Steelers coach Bill Cowher argued the Colts made contact with the linemen, which would have forced an offside call and a first down. Instead, Ben Roethlisberger ran a quarterback sneak for a first down, which allowed Pittsburgh to use another 5:02 before punting. Run the interference On third-and-2 from the Pittsburgh 28 with 25 seconds left, Manning threw to Reggie Wayne in the corner of the end zone, but the play was broken up by rookie Bryant McFadden. Wayne tried going over McFadden for the catch, and Manning was hoping for pass interference — but no penalty was called. The Colts tried a 46-yard field goal, which Mike Vanderjagt missed wide right.