On that September day, Alex Smith (remember him?) led the 49ers to a surprising 30-22 victory over the Packers at Lambeau Field.
Each of these teams has grown and evolved since then, with Green Bay discovering a new offensive star in Randall Cobb and San Francisco making a midseason QB switch in favor of Colin Kaepernick.
So, where do the advantages lie for both teams?
Let's break down some of the biggest matchups within this game and find out who has the edge. At the end we will award one team with the overall advantage and figure out how we got there.
Get it? Got it? Good.
Let's start with the quarterbacks.
It's strength on strength as reigning MVP Aaron Rodgers squares off against the 49ers formidable pass defense.
San Francisco is allowing just 200 yards through the air per game, good enough for fourth best in the regular season.
When these teams met in Week 1, Rodgers had a typically good 303 yards passing with two touchdowns and one interception. San Francisco did have five pass deflections and mixed up schemes, but Rodgers was an efficient 20-of-26 passing.
Playing in San Francisco this week will eliminate any worries of cold weather being an issue, so it will be up to the 49ers to cause pressure and force Rodgers into tough situations. If he has one weakness (if you want to call it that) it is that he will sometimes sit back in the pocket for too long and hope something develops.
San Francisco can not allow Rodgers to take his time, because his receivers will eventually get open and he is deadly accurate when they do.
This QB/Pass Defense showdown is much tougher to gauge because there is no barometer to measure against. Alex Smith was under center for San Francisco in Week 1. Unless the 49ers secretly have a Christian Ponder situation going on, that won't be the case this time around.
Instead, Colin Kaepernick will be seeing his first career playoff action and will attempt to prove head coach Jim Harbaugh right for anointing him the starter midway through the season. Kaepernick's versatility and the variety he brings to the offense is certainly unique and should create some mismatches.
The Packers defense did face a similar mobile threat in Russell Wilson in Week 3. In that contest they held the rookie to just 130 yards passing and 18 rushing yards. However, that game is far from an indicator of how this will go.
Kaepernick has thrown seven touchdowns compared to just two interceptions in the last three games, building solid momentum heading into the postseason. Green Bay does have the 11th-ranked pass defense in all of football, so this should be one of the key matchups in this contest.
There is a slight edge to be had here, and it goes to the young QB that Green Bay has never game planned for.
Ryan Grant and DuJuan Harris split the carries against the Minnesota Vikings in the Wild Card Round and that is likely to be the case again.
Unfortunately it does not make much of a difference who lines up behind Aaron Rodgers because this is one of the most lopsided matchups in the contest. San Francisco has one of the league's best run defenses and the Packers have failed to establish much of a presence on the ground all season.
Harris did manage 47 yards on 17 carries against Minnesota, but the 49ers are an entirely different animal. In Week 1 Green Bay gained 45 yards on 14 carries against San Francisco. Pressure was put on Aaron Rodgers' shoulders early and often in that contest because no one was able to assert themselves as a legitimate threat on the ground.
Ryan Grant has talent and has flashed brilliance before, but to expect much out of him or Harris against San Francisco would be a pipe dream.
Frank Gore rushed for 100 yards in a game just three times all season, but one of those instances was in Week 1 against the Packers.
Gore carried the ball 16 times in that contest and set the pace for a 1,214-yard season. The rejuvenated Gore will again have a chance to take over the contest, as the Packers have allowed over 100 yards on the ground in five of their last eight games.
However, Green Bay does have formidable playmakers in the front seven highlighted by B.J. Raji and Clay Matthews. If Raji can attract double-teams in the middle of the field and Matthews can cause problems off the edge, Gore can be shut down.
Green Bay's rush defense did look good against Adrian Peterson in the Wild Card Round, but that was easy when Joe Webb presented almost no threat throwing the football. It will be interesting to see how the Packers respond to San Francisco's Pistol formation and option attack.
For now, Gore has to be given the upper hand until Green Bay proves otherwise.
Now we will highlight one particularly exciting individual matchup for both teams, starting with Greg Jennings against Carlos Rogers.
Rogers is San Francisco's best cornerback and will likely have the task of shutting down Green Bay's best receiver. Jennings had four catches for 61 yards against the Vikings and looks to be fully healthy as the playoffs wear on.
Back in Week 1, Jennings had just five catches for 34 yards and Rogers seemed to limit his potential for most of the game. Green Bay even lined Jennings up in the slot on multiple occasions, but it was to no avail as Rogers almost single-handedly took him out of the passing game.
The Packers have a plethora of offensive weapons that are clicking right now, so Rogers may not have as many chances at one-on-one coverage. When he does he will have the clear advantage over Jennings.
Vernon Davis and Colin Kaepernick have had a bit of an inconsistent relationship since the rookie took over the offense, but it is safe to assume he will lean heavily on his All-Pro tight end this week.
Green Bay's linebackers limited Davis to three catches for 43 yards and a touchdown in their last meeting, but again, the 49ers offense is completely different at this point in the season. Davis is a tremendous weapon when he is involved in the offense and he can provide problems for the Packers' linebackers.
Green Bay does have a unit built to stop the pass, but Davis' 6'3" 230-pound frame is tough to contain. He is also adept at finding seams over the middle of the field and making tough catches. Still, with Mario Manningham on IR it seems likely that the Packers will pay plenty of attention to Davis and star receiver Michael Crabtree.
Davis is one of the best tight ends in football, but he does not have great chemistry with Kaepernick yet and Green Bay has a talented linebacking corps.
The Packers have seen some small turnover along the offensive front in recent weeks, as Jeff Saturday vacated the center spot to make way for Evan Dietrich-Smith. Smith has performed well in the starting role and will be part of an important battle between the Packers' offensive line and 49ers' defensive line.
Green Bay has fought to establish a rushing attack all season, but has failed to do so in part because this offensive line has struggled at run blocking. Couple that with 51 sacks allowed on Aaron Rodgers and this matchup could be quite lopsided.
Rodgers does cause some of those sacks himself, but the 49ers bring forth some of the best defensive players in all of football in Aldon Smith and Patrick Willis. In Week 1, San Francisco got to Rodgers for three sacks.
Keeping Rodgers upright will be paramount because the rushing attack has little chance of performing.
The 49ers' offensive line has allowed 41 sacks this season and paved the way for a 1,200-yard rusher in Frank Gore. Left tackle Joe Staley is one of the best in football, and San Francisco has a consistent and stable offensive line in place.
There are few question marks along the front five and that will bode well against the talented front seven of the Green Bay Packers. Clay Matthews is the clear star, but there are more than a few Packers capable of making plays in the backfield. In fact, Green Bay had four sacks when these two teams met in Week 1.
San Francisco's line has shown great versatility in adjusting to the play of Colin Kaepernick while being road-graters when necessary and paving the way for Gore.
The 49ers edge is not huge here, but they do have the advantage and Green Bay will have to find a way to disrupt San Francisco's offensive rhythm, timing and flow in order to be successful.
Here is a factor that may go a long way towards deciding the winner of this Divisional Round meeting.
Green Bay will be relying on the inconsistent leg of Mason Crosby to guide them in the field-goal department. Crosby has one of the strongest legs in the NFL, but you never know if he is going to come to play.
Crosby went 21-of-33 on field-goal attempts this season, including three games in which he missed multiple times. The good news is that he has connected on his last five attempts.
For San Francisco this should be a clear advantage, but the kicking of David Akers has been anything but steady in recent weeks.
He is 29-of-42 on the season and has missed four of his last 10 attempts. This is unusual for Akers, but the fact that he, like Crosby, has just two field goals of 50 yards or more all season is the real issue here.
Both kickers are unreliable at this point and the question will be if either proves to be a disadvantage. The nod goes to Crosby only because he is clicking at the right time.
Advantage: Packers (but it's a slim one)
Whenever a television broadcast for an NFL game begins, some insightful announcer always proclaims that special teams is going to be the difference in the game.
Well, whichever announcer gets to that cliche first may actually be right about this matchup. Randall Cobb is one of the best rising stars in the league and has been absolutely electrifying in the return game all season.
Cobb is averaging 25.4 yards per kick return and 9.4 yards per punt return while also scoring one return touchdown this season. He can change the game on one play and San Francisco will have to be smart in how to approach him in this game.
The 49ers will have LaMichael James back deep to return and he has proved to be a great asset in a short amount of time on the roster. The 5'9", 195-pound weapon is averaging 29.8 yards on 14 kickoff returns this season.
James is exciting, but he does not yet have the body of work that Cobb does.
Ah, yes, momentum. That scary word that some people believe in and others consider to be hogwash or malarkey.
Well, if you are a believer in the fickle science of momentum then you would see that both teams clearly have it.
Green Bay is riding high after shutting down Adrian Peterson and winning a showdown with their bitter division rivals. The Packers have now won 10 of their last 12 games since starting the season 2-3.
Likewise, San Francisco has been red hot entering the postseason. The 49ers are 7-2-1 in their last 10 games, including five wins by double digits.
In other words, there is no real advantage when it comes to momentum.
The Green Bay Packers are constantly battered and bruised, but they brought almost everyone to play against the Vikings. That should not change against the 49ers.
Charles Woodson, Jordy Nelson, Tramon Williams and Randall Cobb all battled through minor injuries to take the field. The lone sore spot came from Jerel Worthy missing the game due to a knee injury.
For the 49ers, Trenton Robinson, Will Tukuafu and Justin Smith are all listed as questionable for the Divisional Round. If Smith for some reason can't go it will be a huge blow for the 49ers, but that would be a complete and utter shock to everybody.
Assuming he plays, San Francisco has to have the edge here because it is simply not as beat up as Green Bay.
The San Francisco 49ers went 6-1-1 at home this season which means the Green Bay Packers should have a daunting task in front of them.
Traveling across the country is never an easy proposition, especially when Green Bay just asserted its dominance within the friendly confines of Lambeau Field. Couple that with the fact that the Packers went just 4-4 on the road this season and the pointer clearly heads in San Francisco's direction.
Jim Harbaugh won the Week 1 meeting between these two coaches. Beyond that fact, Mike McCarthy has every advantage possible on Harbaugh.
McCarthy has coached in big games before and won a Super Bowl. Green Bay has gone through the playoff rodeo for four years now and knows everything that can be thrown its way. Harbaugh and the 49ers, on the other hand, are making just their second playoff appearance and are starting a young QB.
McCarthy has a QB that he can trust and rely on in the most crucial of moments and defensive leaders that know what it takes to win in the postseason. These are both great NFL coaches that have done tremendous things for their organizations, but McCarthy has hoisted the Lombardi Trophy.
Harbaugh still has work to be done before he evens this matchup.
Packers: five advantages
49ers: seven advantages
One matchup is even
Overall Advantage: 49ers
The final tally indicates that San Francisco holds a slight edge over Green Bay when the most important matchups are broken down.
These are two drastically different football teams and yet each of their styles has suited them well on the way to the postseason. Some of the most intriguing matchups of this game will come from Colin Kaepernick against the Packers pass defense and the battle between the respective place kickers.
If one team wins both of those showdowns it will go a long way toward moving on to the NFC Championship Game.