Defense is dominant in this Super Bowl.
While the NFL has been built around the offense in recent years, defense is a big part of these two Super Bowl teams.
The Ravens sport one of the most veteran defenses in the game, while the 49ers are one of the most athletic.
When it comes down to physically domineering defenses, it's difficult to determine if San Francisco's or Baltimore's is the top D.
But one thing is for sure; both teams love to hit the opposing players.
For the 49ers, there's a threesome of linebackers that will hit you so hard your head will ring.
San Francisco employs the 3-4 defensive scheme, much like Baltimore, and those athletically gifted linebackers do all the damage.
Aldon Smith is a pass-rushing monster; he accounted for a second-best in the NFL 19.5 sacks in the regular season, though he's yet to sack a quarterback in the playoffs.
Patrick Willis is the unquestioned leader of the D, and he's put up 19 tackles with a sack and a stuff in San Francisco's two playoff contests. He not only calls the plays out to his teammates, but leads by example; when Willis is on his game, the 9ers are hard to beat.
And the guy you've never heard of is NaVorro Bowman, a third-year man that is every bit the devastating tackler as his teammates. Bowman's a real beast, leading the team with 149 total tackles in the regular season and 10 tackles, with three passes defended in the playoffs.
Don't forget about physical and veteran cornerbacks Carlos Rogers and Tarell Brown, who combined for 112 tackles and three picks in the regular season, with one INT and four passes defended in the postseason.
The 49ers specify in stopping the run, and Ray Rice will be enemy No. 1 for them come Sunday. Rice has been known as one of the league's most dangerous backs, but also one that has a tendency to disappear in big games as well. If they can slow down Rice, it all falls in the hand and right shoulder of Joe Flacco, who's been spectacular all postseason.
Super Bowl XLVII kicks off at 6:30 p.m. ET on Sunday, February 3 and can be seen on CBS.
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