Sunday's NFC Championship game will represent the biggest stage the 49er/Seahawk rivalry will ever have. For anyone who has watched these teams this year, it shouldn't come as a surprise that they are the final two standing in the conference. Seattle and San Francisco are far and away the strongest teams on the NFC side of the bracket, and they will clash for the 3rd time this season. While San Francisco has struggled in Seattle the last two years, they are the hottest team in the NFL right now and boast one of the few rosters that has the ability to defeat the Seahawks on their own turf.
It's going to be loud. It's going to be tough. And it's going to be the most intense game any of these players have ever played in, but the 49ers will win this game if:
The defense slows down – and brings down – Marshawn Lynch: What makes Lynch so tough is his ability to fight for the extra yards. He is able to take a seemingly short gain and turn it into a game changing run with his ability to break tackles. That toughness and aggression pays off when defenders try to knock him down with a big hit instead of wrapping him up. Many of his long gains are a result of a defender not having the strength or proper tackling to bring him down at the point of impact. Lynch delivers hits as much as he takes them, so if a defender is one on one with him, the 49ers need to swarm to the ball and take him 
down with multiple bodies, as he will fight for every last yard he can get, often out-muscling the bodies in front of him. The difference in that extra yard or two is going to be a factor as the game goes along.
The 49ers have had mixed results in defending Lynch this season. He posted 135 total yards and 3 touchdowns in Seattle's week 2 blowout victory. However, in the 49ers week 14 win, Lynch was held to just 72 yards and a goal line touchdown run. By now, San Francisco knows what to expect from Lynch and the running game, they just need to make sure they wrap him up and make a good tackle, rather than delivering shots to his upper body.
The team keeps its emotions in check: Things got pretty chippy post-play against a physical Carolina team last week. The same is going to happen this week, as every matchup between Seattle and San Francisco is notoriously physical. Both teams have had their share of personal fouls and unsportsmanlike conduct penalties, and with emotions 
running high it will be that much tougher to walk away from confrontation.
Specifically in the case of Anquan Boldin and Donte Whitner, they need to be careful about how they react after the play. Boldin was lucky to get away with a headbutt last week; one that looked awfully similar to the one Carolina's Captain Munnerlyn was flagged for. Whitner did a lot of post-play jawing with Lynch in the most recent meeting, and made contact with him more than once. You can't fault them for being passionate, but both players have a reputation for getting too carried away, and you can be sure Seattle is going to seek them out (and every 49er) in order to provoke them into a penalty. San Francisco can't give up yards on avoidable penalties like that.
The offense establishes a rhythm early in the game: San Francisco has scored on their opening possession in 5 straight games, including 3 consecutive games where they scored on back-to-back drives to open the game. It's not a coincidence that the offense has found some solid production in both yardage and points during that streak. They need to continue that trend on Sunday. Not only does an early score give the offense some confidence and ability to find a rhythm – something the 49ers have not done well in Seattle 
– but it will also keep Seattle's 12th Man from getting overwhelmingly loud early on.
While the offense doesn't absolutely have to score on it's first drive or two, they need to at least pick up some first downs, give Gore a nice run or two, and allow Kaepernick to complete a few passes. What they want to avoid are the quick three-and-out's, where no one gets a chance to settle into the flow of the game. The offense can set the tone in the first handful of drives and impact how Seattle plays them defensively. If San Francisco comes out shaky, the Seahawks are going to get aggressive and try to force Kaepernick into a mistake. A quality drive or two will force them to respect the offense and play a bit safer, which gives the 49ers a better chance to control the ball.
They keep mistakes to a minimum, forcing the Seahawks offense to make plays: Seattle's offense has fallen into a bit of a funk in the last few games. A big part of their success last week came from New Orleans turnovers and mistakes that set them up with great scoring opportunities and a short field. Despite scoring 23 points, the 
performance of Russell Wilson and the offense, outside of Lynch, was not up to par for a Super Bowl contender.
The Seahawks possess some talented players on the offensive side of the ball, but this is a team that relies heavily on the defense and special teams to help create a short field for the offense. The 49ers have played a pretty clean postseason so far, turning the ball over just once in two games. Avoiding mistakes and forcing Wilson and the Seahawks offense to put up points on their own is going to be crucial in winning the game. It will probably take between 17-20 points to win this game for either team, so San Francisco must not allow those points to be scored when Seattle doesn't even have the football.
Boldin and Crabtree rise to the challenge: The top two receivers in the offense are rolling and seemingly feeding off of each other's performance. A week after Crabtree posted an 8 catch, 125 yard effort in Green Bay, Boldin contributed an almost identical stat line of 8 catches for 136 yards last week. Crabtree has never had much success against Seattle in his career, with 27 receptions for 298 yards in 8 games. That's roughly a 3 rec/37 yd per game production. Crabtree isn't as physical of a receiver and struggles to get separation in his routes when matched up against an aggressive Seattle secondary. 
However, he has never faced them with Boldin lining up opposite him.
Boldin's size and physicality gives him the ability to gain space off the line of scrimmage and fight for the contested ball downfield, something that is necessary against big-bodied Richard Sherman and Brandon Maxwell. With Crabtree and Boldin healthy, Seattle will have to account for both of them for the first time ever. Seattle has arguably the best secondary in the league, but being able to spread them out against receivers with very different styles will give Kaepernick the chance to find a favorable matchup. While it has been largely one or the other since Crabtree and Boldin were both in the lineup, it's going to take an effort from both of them in order to prove effective through the air, something San Francisco has struggled with versus Seattle in the Kaepernick era.
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