At this stage of the NFL playoffs, it is not always the big stars who decide games. Instead, lesser-known players always seem to step up to make all of the difference.
This year, the Baltimore Ravens will take on the New England Patriots in the AFC Championship Game. While Tom Brady and Ray Lewis are certain to play an important factor for their respective teams, there are other players who can and will affect the contest just as much.
These X-factors will either lead their team to victory with a big performance or cost their team with a dud.
Here are the biggest X-factors for this upcoming matchup.
Devin McCourty, S, New England Patriots
Few players on the field will be more important in this game than Devin McCourty.
The struggling cornerback moved to safety during the season and has played very well in his new spot. He has great closing speed to help in coverage and he recorded five interceptions during the season.
This ball-hawking ability will be very important against the Ravens, who like to throw the ball downfield often to both Torrey Smith and Anquan Boldin.
If McCourty can provide deep help to his cornerbacks, then he has the ability to take away these game-changing plays.
In addition, the safety is also the Patriots kick returner. After what Trindon Holliday did to the Ravens last round, do not be surprised to see McCourty have a huge impact on special teams as well.
Shane Vereen, RB, New England Patriots
There is no running back controversy; Stevan Ridley is still the starter in New England. However, Shane Vereen picked a great time to have his best career game.
Against the Houston Texans in the Divisional Round of the playoffs on Sunday, the second-year player had 41 rushing yards and a touchdown to go along with 83 receiving yards and two more touchdowns.
The only time in his career that he had more total yards in a game was against the New York Jets, which included an 83-yard catch and run for a touchdown.
With Rob Gronkowski out for the playoffs (via ESPN), Tom Brady is running out of people that he can trust. Vereen proved last game that he can be trusted in important situations.
He will not be able to replace the Pro Bowl tight end, but he is yet another offensive weapon that could hurt the Ravens in this contest.
Paul Kruger, LB, Baltimore Ravens
Terrell Suggs woke up last game and gave the Ravens a huge boost against the Denver Broncos by finishing with 10 tackles and two sacks.
However, the most consistent pass-rusher on this team throughout the season has actually been Paul Kruger. He is the one that must step up against the Patriots on Sunday.
Kruger finished the regular season with a team-high nine sacks. He then had 2.5 sacks in the team's opening-round playoff win over the Indianapolis Colts.
Suggs has clearly been less than 100 percent this year, so Baltimore needs others to get to the opposing quarterback and throw opposing signal-callers out of their rhythm.
Against the Broncos, Kruger had no sacks but did manage to tally two clean hits on Peyton Manning, and this was enough to rattle the veteran quarterback. If he can do the same against Brady, it will give his team a chance to slow down the offense and eventually win this game.
Justin Tucker, K, Baltimore Ravens
In his rookie season, Justin Tucker has been simply amazing. He made over 90 percent of his field-goal attempts during the regular season, including 4-of-4 from over 50 yards.
He also passed an important test by successfully kicking the game-winning field goal in double overtime against Broncos on Saturday.
However, all he needs is one bad miss to make everything that he accomplished this season rendered meaningless.
Last postseason, the Ravens were three points away from sending the AFC Championship Game into overtime, but Billy Cundiff missed a 32-yard field goal. Baltimore might burn to the ground if something similar happens again this year.
Tucker has shown confidence in every kick this year. However, the pressure grows every week.
If he has to make a kick to tie or win the game, the team better hope that he acts like a mature veteran instead of a 23-year-old in his first postseason.
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