Both teams have experienced several close-but-no-cigar moments in the past decade and a half amid steadily changing casts of characters - Jeff Garcia, Michael Vick, Terrell Owens, Keith Brooking, Julian Peterson and Alge Crumpler are among the crews who never quite got it done. But a week from now, one of these franchises will be back in the Super Bowl for the first time since the 1990s, when they used to be NFC West rivals (Atlanta in the NFC West always made so much sense, but that's another story).
Here are five story lines to watch:
5 story lines: AFC Championship Game
1. Hello again: They last played in 2010, so both clubs will be getting reacquainted in the film room. The Falcons won a tight 16-14 game in the last meeting after Roddy White stripped an interception from former Niners corner Nate Clements, a precursor to Matt Bryant's game-winning field goal in the closing seconds. San Francisco has since been overhauled - coach Jim Harbaugh and starting quarterback Colin Kaepernick were still in the college ranks in 2010 - and the Falcons, though they retain many of the key personnel from the previous matchup, are far different schematically under coordinators Dirk Koetter (offense) and Mike Nolan (defense), who both came aboard for the 2012 season. Don't be surprised if there's an extended feeling-out process for both teams in Sunday's opening quarter.
2. Lessons learned: Their lack of familiarity aside, these teams each got helpful tune-ups in the divisional round that should provide key lessons moving forward. San Francisco gave up plenty of chunk plays to Aaron Rodgers and the Green Bay Packers on Saturday and narrowly avoided getting burned additional times, including a late pass Greg Jennings failed to haul in with the outcome in doubt. The Falcons may not have a suite of weapons as diversified as Green Bay's, but Matt Ryan has a better trio of receivers in White, Julio Jones and Tony Gonzalez and probably a better backfield (Michael Turner, Jacquizz Rodgers). Ryan himself is not yet on Rodgers' level and must make hay against another defense layered with hazards to get there. Kaepernick may be salivating after Atlanta's bend-and-sometimes-break defense was deconstructed by the Seattle Seahawks' Russell Wilson, another multi-faceted quarterback. Kaepernick is a more dangerous runner than Wilson and has a stronger arm but might be more prone to a crucial mistake, though he lived to tell about the pick six on the opening drive vs. Green Bay. Like the Packers, the Falcons are built around their nickel defense, so look for Kaepernick to do plenty of tucking and running while giving Frank Gore a steady diet of work.
3. On the rebound: After enduring his least productive season (800 rushing yards) among his five in Atlanta, Turner rumbled for 98 Sunday. Running against the Niners is no easy task, but balance makes the Falcons' aerial show even more imposing. San Francisco tight end Vernon Davis has essentially been a forgotten man himself with just seven catches in the past seven games, though he did haul in a 44-yarder Saturday to set up a touchdown. It's worth noting Kaepernick targeted him five times, so Davis (who suffered a concussion in Week 16) may be ready to emerge as a complement to red-hot Michael Crabtree. And the Falcons had little luck stopping Seahawks tight end Zach Miller, who isn't nearly the mismatch Davis is, not to mention wideout Golden Tate. It would help if Atlanta pass rusher John Abraham can shake off his balky ankle.
4. Underrated: Three first rounders man the 49ers offensive line, a unit which has adjusted beautifully on the fly to Kaepernick and left him many green pastures to gallop into. Left tackle Joe Staley may not be 100% after getting banged up vs. the Packers, but the man he'll be blocking - Abraham - isn't in peak form, either. Atlanta's defense was middling in most categories all season but thrived in two key ones under Nolan: it surrendered the fifth-fewest points in 2012 while finishing plus-13 in turnovers. It managed two more takeaways from a Seattle team that hadn't committed two turnovers in one game since Nov. 11. Exploiting Kaepernick's inexperience (8 NFL starts) may be a prerequisite to victory, though he proved last weekend that he doesn't rattle even when he screws up.
5. Tone-setters: Keep an eye on 49ers Pro Bowl safeties Dashon Goldson and Donte Whitner. Whether it's sprinting into the box to lay a lick on Turner or trying to level a pass catcher between the hashes, they'll try to send a message early that they're the physically dominant team. White and Atlanta defenders Sean Weatherspoon and Asante Samuel may look to influence matters themselves with their sometimes prickly play and mile-a-minute mouths.
Why the 49ers will win: Kaepernick looked unstoppable in his playoff debut while more than answering every naysayer who questioned his midseason promotion ahead of Alex Smith. The defense has lost its air of dominance, but it sure looked more effective with Justin Smith (triceps injury) back in the lineup than it did at the end of the regular season ... though it'd be nice if Aldon Smith returned from a recent stint in witness protection. But Kaepernick remains the key, and if he continues protecting the ball, he'll be one step closer to etching his name alongside Joe Montana's and Steve Young's.
Why the Falcons will win: Their bread-and-butter passing approach should work far better in the friendly confines of the Georgia Dome than it would have at Candlestick Park. With Turner seemingly rediscovered and Gonzalez able to work the seams, they should keep the Smiths and star linebackers Patrick Willis and NaVorro Bowman plenty busy while creating room for White and Jones with at least one of them enjoying single coverage. Another fast start like the one against Seattle would obviously help, especially since Kaepernick has been more uneven on the road. And if it comes down to a sudden-death situation, Bryant has been a deadeye kicker in such situations while counterpart David Akers has struggled lately.
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