Justin Smith and Co. led the 49ers to a 23-10 win over Carolina on Sunday.
The 49ers shut out the Panthers in the final 30 minutes. Overall, they sacked Cam Newton five times and intercepted him twice.
They left no doubt that they had the better defense on the field.
One day prior, the Seattle Seahawks made a statement. Against the high-powered New Orleans Saints, the Seahawks allowed just 15 points—including a garbage-time touchdown in the last minute of the game.
In the NFC Championship Game, the two best defenses in the league will square off.
Though they are both effective, they go about it in two different ways.
Seahawks: Best Secondary in the League
The Seahawks have, far and away, the best secondary in the NFL. Whereas the 49ers often leave two safeties back to help on deep passes, the Seahawks trust free safety Earl Thomas to protect the field from sideline to sideline.
Strong safety Kam Chancellor often starts plays close to the line of scrimmage, giving Seattle an extra man in the box. This helps the Seahawks stop the running game and affords them more options in their blitz packages.
The Seahawks can get away with selling out against the run because they have the best cornerback corps in football. You all know about Richard Sherman, but Byron Maxwell and Walter Thurmond are very effective as well.
All three were ranked in the top 31 of Pro Football Focus' regular-season cornerback rankings (there were 110 eligible CBs).
The trio led Seattle to top per-game marks in passer rating against (63.4) and passing yards allowed (172).
The Seahawks also led the league in interceptions (28) and yards per attempt allowed (5.8).
Seattle's run defense isn't chopped liver, either. It ranked No. 7 in yards allowed per game (101.6) and yards allowed per attempt (3.9).
|Passing YA||Rushing YA||Turnovers||Scoring|
|Seattle||172 (1st)||102 (7th)||39 (1st)||14.4 (1st)|
|San Francisco||221 (7th)||96 (4th)||30 (6th)||17.0 (3rd)|
So how do you move the ball against Seattle's defense?
Opposing offenses have to take advantage of Seattle's press-man, one-on-one coverage. If they do, then they can force Seattle's linebackers and Chancellor to focus more on the pass game, which should open up the running game more.
It's much easier said than done. Sherman is the best press-man cornerback in the NFL. He was largely responsible for Anquan Boldin's struggles in Week 2 (one catch, seven yards) and Michael Crabtree's pedestrian performance in Week 14 (four catches, 40 yards).
The 49ers might have found something by targeting Boldin in Week 14 (six catches, 93 yards). Even with Boldin's success, Colin Kaepernick's net average was just 5.3 yards per attempt.
As important as Frank Gore and the rushing attack is to San Francisco, the 49ers aren't going to beat Seattle if they don't win some one-on-one battles against the Seahawks' secondary.
49ers: Best "Front Six" in the League
The 49ers lean on their nickel defense more than any team in the league. They use three cornerbacks to defend the other teams' three best receivers, which leaves them with six linebackers and defensive linemen combined on the field.
Even in this defensive formation, they stop the run.
Whereas most teams need at least seven in the box to slow down a running game, the 49ers rely on inside linebackers Patrick Willis and NaVorro Bowman (along with four defensive linemen) to contain opponent ground attacks.
And it works. The 49ers were fourth in rushing yards allowed per game (95.9) and ninth in rushing yards allowed per attempt (3.9) in the regular season.
What's even better about Willis and Bowman is they double as quality pass defenders against tight ends.
The 49ers allowed 747 yards to tight ends in the regular season, which ranked eighth in the NFL, per FFToday. They've allowed just 63 yards to tight ends so far in this postseason.
The one area of the 49ers defense that gets exposed most is the secondary, though it's still a great unit.
The Niners ranked sixth in yards per attempt allowed (6.5) and fourth in passer rating against (76.4) in the regular season.
Defensive coordinator Vic Fangio rarely ever calls for blitzes. According to John McTigue of ESPN.com, the 49ers sent an extra rusher less often than all but one team in the regular season. This strategy has its strengths and weaknesses.
Which team has the better defense?
It allows safeties Donte Whitner and Eric Reid to defend their deep halves of the field on most plays. With both safeties back, the 49ers are able to limit the amount of big plays against them.
The negative is when their front four doesn't apply consistent pressure on the opposing quarterback, he can get comfortable and beat them with short and intermediate routes.
To beat the 49ers, opposing offenses need to establish a running game against San Francisco's front six. If they can get the 49ers linebackers and safeties to focus more on stopping the run, then they can take advantage of San Francisco's cornerbacks in man coverage.
Marshawn Lynch is one of the only running backs in the league who has consistently had success against the 49ers. In Week 14, the 49ers sold out on Lynch several times, which opened up the Seattle passing game.
On a play-action pass in the second quarter, Russell Wilson found tight end Luke Willson wide open behind San Francisco's linebackers and safeties for a 39-yard touchdown.
Even with their attention on Lynch (20 carries, 72 yards), Wilson finished with 7.1 net passing yards per attempt. If the Niners make Lynch their top priority, the Seattle receivers have to take advantage of man coverage against San Francisco's corners to move the ball consistently.
The Seahawks are the more aggressive defense. They're more likely to blitz and leave their secondary vulnerable. They're going to force Colin Kaepernick to make quick decisions to beat them.
Meanwhile, the 49ers have shown time and again that they can get pressure with their front four. They're more likely to keep Russell Wilson in the pocket and force him to make very accurate throws against their back seven.
Neither Kaepernick nor Wilson has had much success in the two regular-season games between the NFC West rivals this season:
The team with more rushing yards has won both games, so expect both teams to key on the running game early.
It will be up to the quarterbacks to find a rhythm. If the defenses have to honor Wilson and Kaepernick, that will open up the running lanes for Gore and Lynch.
The stats suggest that the Seahawks had a slightly better defense in the regular season. But the 49ers defense has raised its level up a notch in the playoffs.
In a week, we'll know which one is going to Super Bowl XLVIII.
Joseph Akeley is a San Francisco 49ers Featured Columnist. Follow him on Twitter.