As the postseason wears on, we've already seen X-factors play huge parts in deciding games and that will be no different in the conference championship games.
While the biggest stars, such as Matt Ryan, Tom Brady and Ray Lewis will make their mark on the game in a major way, the games are usually decided by impact performances from players who you wouldn't always expect them from.
In other instances, some of the most talked about players can either emerge with huge performances or fall flat and cost their team a chance at a Super Bowl.
Here's one X-factor for each team in the AFC and NFC championship games.
Atlanta Falcons: LB Stephen Nicholas
Going up against a very versatile San Francisco 49ers offense, the Falcons defense will have their hands full. But no defender needs to step up more than linebacker Stephen Nicholas.
The 29-year-old from South Florida has been a major cog in Atlanta's defense this season, notching 97 tackles on the season and amassing five in their thrilling victory over Seattle last weekend. He played a huge part in keeping scampering rookie quarterback Russell Wilson contained.
As if containing Wilson wasn't tough enough, they face an older, more athletic and more polished version of him in Colin Kaepernick this weekend. The 49ers quarterback gashed the Packers defense for nearly 200 rushing yards and set a NFL playoff record in the process.
If Kaepernick doesn't have the luxury of escaping outside the pocket, he's much more uncomfortable and can be forced into making bad decisions. Much of that responsibility will fall on Nicholas, who will likely be used as a QB spy in this one.
It will take a collective effort to keep Kaepernick contained, but no one will be more responsible than Nicholas.
San Francisco 49ers: RB Frank Gore
49ers running back Frank Gore is perennially seen as one of the NFL's best rushers, and that's still the case. But his 100-yard performance Saturday night against Green Bay was only his third such game this season.
While Kaepernick got all of the credit and glory, Gore's 23 carries for 119 yards and score as well as 48 receiving yards helped San Francisco carry the load and sustain drives when Green Bay was still within striking distance.
It's not uncommon to see a scrambling quarterback have one magnificent game and then find no such luck in the following game. It's not too hard of an adjustment to make when you have a week of film to watch.
For that reason, Gore must come into this game ready to carry the load on the ground and not rely on Kaepernick to do anything but throw the ball. If he does that and succeeds, San Francisco will be in the Super Bowl come February 3.
New England Patriots: RB Shane Vereen
While the Patriots won't be making any massive changes in their starting running back rotation, third-stringer Shane Vereen made a name for himself in New England's victory over Houston on Sunday.
The former Cal Golden Bear picked up 83 yards through the air and two scores to go along with 41 rushing yards and another TD. He was the story of the Pats' victory.
Ridley will still carry the ball more, but Vereen can be featured more as a receiver now that prized tight end Rob Gronkowski is out of the playoffs (per ESPN).
We all know that Wes Welker will be consistent, but Brady will be hesitant to put the ball in anyone else's hands in such a huge game. Though after the game Vereen had on a huge stage, he'll feel more comfortable looking his way more often and the coaches will reward him for his stellar game last weekend.
Baltimore Ravens: LB Terrell Suggs
Thanks to having an all-time great and transcendent player in Ray Lewis playing in his final postseason alongside him, Terrell Suggs won't have many cameras on him and won't be talked about very much by the commentators.
But realistically speaking, he'll have a bigger impact on this game if you count out the emotional factor.
Against Denver, Suggs had a huge game with 10 tackles and two sacks, as he tormented Peyton Manning all game long. Otherwise, the Ravens would've had no business in overtime against one of the Super Bowl favorites.
Against another elite quarterback in Tom Brady, Suggs will have to step up his game even further to extend his popular teammate's career by one more game.