Their success proved a big-play quarterback wasn't a necessity, that ferocious defense, superb special teams and a running game were sufficient to the cause.
A lot of teams bought into that concept this season, especially in the AFC. The NFC features prolific quarterbacks - the St. Louis Rams' Kurt Warner, Green Bay Packers' Brett Favre, San Francisco 49ers' Jeff Garcia - while the AFC features defense and running games, with just a few notable exceptions.
That circumstance has made for one of the most wide-open playoff races in the AFC. With seven weeks left in the regular season, 10 teams are at .500 or better (compared with eight in the NFC). Four teams in both the AFC East and West are jockeying for playoff position. Five teams in the AFC Central, including the Cincinnati Bengals and Tennessee Titans at 4-5, still have designs on a playoff berth.
In a season that already has stretched the imagination with stunning upsets and breathless comebacks, any one of a number of teams could sneak into the playoffs via the wild-card route and attempt a Ravens-like coup.
The Seattle Seahawks, for example, have the easiest finishing schedule in the NFL at this point. There's not a winning team remaining on their schedule. If the playoffs started today, the Seahawks would draw the No. 6 seed by virtue of their Week 1 win over the Cleveland Browns, who are also 5-4.
Contrast that with the Indianapolis Colts, who have six winning teams left and face the hardest stretch-run schedule. Their opponents have won 44 of 66 games, a winning percentage of .667. The injury-depleted Colts must make road trips to Baltimore, Miami and St. Louis in the next five weeks.
Don't count on them to be the team that sneaks in.
Here is a breakdown on the 13 AFC teams looking at six playoff spots.
Pittsburgh: The Steelers rank fourth in offense and first in defense. Quarterback Kordell Stewart is completing 60.5 percent of his passes and looks like he finally made the turn in a checkered NFL career. It's Pittsburgh's suffocating defense, though, that promises to keep the Steelers in the running for home-field advantage. Like the Ravens a year ago, they've remained relatively injury free.
Oakland: The Raiders' offensive line has been hampered by injuries, and cornerback Charles Woodson has a troublesome turf toe injury. But the Raiders have some of the best depth in the NFL, and they've got a quarterback, Rich Gannon, who's extremely protective of the ball. He's thrown just two interceptions in 295 passes. The Raiders are the only team still undefeated at home.
New York Jets: The Jets rank 29th in run defense and pass offense, yet lead the AFC East at 7-3. That's because they're plus-22 in turnover ratio with an astounding 33 takeaways. (The Ravens led the league last season with plus-23.) Curtis Martin leads the league in rushing. If quarterback Vinny Testaverde gets hot, they could be real trouble.
Seattle: An injury to Ricky Watters gave Shaun Alexander a chance, and the second-year running back made the most of it. The Seahawks' defense is significantly improved over last season. Alexander's arrival has bought time for first-year starting quarterback Matt Hasselbeck. Don't forget Trent Dilfer is on the bench.
Ravens: Despite quarterback Elvis Grbac's turnover binge, the Super Bowl champs have found inventive ways to win. Their recent three-game winning streak easily could have been a losing streak. Injuries, though, appear to be catching up to the Ravens. Sooner or later, Grbac has to eliminate the turnovers.
Cleveland: At 5-4, the Browns must be doing it with mirrors. Their offense ranks last in the league, but their defense is opportunistic. They're plus-12 in turnovers, second-best in the league. The sweep of the Ravens is big.
New England: Many felt the loss of quarterback Drew Bledsoe to injury in Week 2 spelled doom. Instead, it triggered a turnaround behind second-year man Tom Brady, who is 5-3 as a starter. Brady has been in a slide the past two weeks, so the Patriots may yet need Bledsoe. They're still a long shot.
Indianapolis: Even without Edgerrin James, the Colts are still capable of scoring points. But they appear incapable of stopping anyone. Their defense has held a team under 300 yards only once this season. And now the injuries are taking a poll. They have to finish 5-2 to even have a chance at the postseason.
Miami: The Dolphins are third in defense, 18th in offense, and last in turnovers (minus-14). Quarterback Jay Fielder is a turnover machine with 15 interceptions. His lack of accuracy has helped hold Lamar Smith to a 2.9-yard rushing average.
Denver: Injuries have robbed the Broncos of their best offensive threats - wide receivers Rod Smith and Ed McCaffery and running back Terrell Davis. They've won only two of their past six.
Tennessee: The loss of running back Eddie George (2.8 average carry) as a viable weapon has had a domino effect on the offense. The defense is battered.
San Diego: Quarterback Doug Flutie's magic apparently has worn off. The Chargers have lost three in a row and five of seven. But 5-5 is still a big jump from 1-15.
Cincinnati: Quarterback Jon Kitna is an improvement over Akili Smith, but not the playoff answer. The Bengals have been shut out in the second half of their past two games (33-0), both losses. At least they're competitive this season.