In middle school, we learned that "X" represents a variable whose value is unknown or secret.
As I start to look at the wild card matchups this weekend, it is inevitable that a handful of unsung players will play key roles in the fate of their respective teams.
These "X-Factors", as I like to call them, range from starters to situational players, but their performance will undoubtedly have a significant bearing on the outcome of the game.
With that thought in mind, let's take a look at the players who will play critical roles this weekend:
Bengals: WR Andre Caldwell
The Bengals' offense has relied extensively on its ground attack throughout the season, but their playoff fate will undoubtedly rest on the success of their passing game. With Darrelle Revis expected to lock down Chad Ochocinco, Carson Palmer will turn to Caldwell in clutch situations. The third-year pro has come up big with the game on the line this season, catching game-winning touchdowns against the Steelers and Ravens, and has been one of Palmer's favorite targets on third down. With the Jets sure to bring pressure from all angles, Caldwell must consistently win his one-on-one matchups to give Palmer a dependable outlet against the blitz. If he can make a few plays in key situations, the Bengals will have a chance to sustain drives and keep the ball away from the Jets' offense.
Jets: DT Sione Pouha
The Jets' suffocating defense is predicated on stopping the run, and Pouha has quietly emerged as a force in the middle. Although he doesn't rack up splashy plays from his position, Pouha's ability to control the middle of the line allows the Jets' linebackers to run free to the ball. Against a Bengals offense that is intent on pounding the ball between the tackles, the fifth-year pro must own his gap and force Cedric Benson to bounce outside to awaiting defenders. If Pouha wins his battle against the Bengals' interior threesome (both guards and the center), the Jets will be able to impose their will on Palmer and Co.
Eagles: WR Jeremy Maclin
The Eagles' big-play offense has struggled in the two previous matchups with the Cowboys, so it is imperative that one of the team's playmakers steps up to deliver a big game. While most will look to DeSean Jackson to provide the spark, it's Maclin who will likely have the best opportunity to make big plays. The rookie finished the regular season ranked third among rookies in receptions and yards, and his ability to get deep gave Donovan McNabb another option in the passing game. The Eagles have cleverly used bunch formations to put Maclin on overmatched safeties in space, and I would expect them to use some unique looks to get their star rookie isolated with Gerald Sensabaugh or Alan Ball. The Eagles have been one of the league's best deep ball teams, and Maclin will need to come down with a few big passes for Philly to win a tough game on the road
Cowboys: OLB Anthony Spencer
The Cowboys' defense has been outstanding down the stretch, and it has been the vastly improved play of Spencer that has keyed the surge. The third-year pro has proven to be an effective rusher opposite DeMarcus Ware, and his ability to get to the quarterback has forced opponents to change the way they attack the Cowboys. The Eagles, in particular, had no answer for dealing with Ware or Spencer off the edges. With Philly sure to focus their attention on stopping Ware, the onus falls on Spencer to wreak havoc off the corner. He was certainly up to the challenge last week (two sacks and a forced fumble), but he has to answer the bell again in the rematch.
Patriots: TE Benjamin Watson
The loss of Pro Bowl wide receiver Wes Welker will force the Patriots to tweak their game plan, and the biggest beneficiary of the change should be Watson. The ultra-athletic tight end has the speed of a receiver and is a potential match-up nightmare in space. The Patriots will likely use more multiple tight end sets with Chris Baker and Watson, but feature more spread or empty formations to get Watson matched up on a linebacker in space. Additionally, Watson's role in the red zone will increase, as the Patriots will use more crossing routes to get their big target open over the middle of the field. This has been a staple in their offense for years, and I would expect them to go back to it with Welker out of the lineup. Watson's numbers haven't been spectacular this year, but look for him to play a critical role against the Ravens.
Ravens: RB Willis McGahee
The six-year veteran had a breakout game against the Raiders last week, as he rushed for 167 yards and scored three touchdowns. His emergence as a complement to Ray Rice has encouraged the Ravens to go back to the "grind it out" philosophy that worked so well for the team last season. With the Patriots' banged up along the front line, Ravens' offensive coordinator Cam Cameron will surely turn to his one-two punch of Rice and McGahee to pound the ball between the tackles. Although Rice has been spectacular as the feature back all season, it is the hard-nosed running style of McGahee that should be most effective when the Ravens turn to their power game in New England. (In the early season matchup, McGahee tallied only 11 yards and came up short on a critical fourth-and-1 in the game's closing minutes). However, if he is able to find success on his 12-15 carries, the Ravens could be well on their way to an impressive win on the road.
Packers: TE Jermichael Finley
The Packers' potent passing game features Pro Bowl-caliber playmakers in Donald Driver and Greg Jennings, but the rapid development of Finley has made the offense nearly impossible to stop. Finley, who ranks as the team's third-leading receiver with 55 receptions, is an athletic freak with an uncanny penchant for getting open in the middle of the field. His rare combination of size and athleticism makes him a tough guard for linebackers or safeties, and the Packers' clever deployment of the second-year pro in spread formations creates mismatches in space. Additionally, Finley's ability to outjump smaller defenders makes him the ideal threat in the red zone. And the Packers will repeatedly attempt to hit him on fades or fade stops once they reach the Cardinals' 10-yard line. With the Cardinals forced to respect the Packers' deep receiving corps, it may be the performance of Finley that leads the team to a win.
Cardinals: RB Chris "Beanie" Wells
The Cardinals remain one of the most explosive passing offenses in the league, but the gradual improvement of the running game could create a host of problems for the Packers. Wells has rushed for more than 68 yards in three of the team's last four games, and his ability to do the dirty work between the tackles has alleviated some of the pressure on Kurt Warner. The Cardinals must establish the run threat to keep the Packers from revving up the pressure on early downs. If Wells can get 15 or more carries with moderate success (at least four yards per carry), the Cardinals will be able to keep the Packers on their heels and off Warner in the pocket.