HOUSTON -- From the personnel to the style of play, the Atlanta Falcons and New England Patriots couldn't be any more different on defense. The Falcons are one of the fastest defenses in the NFL and have an it's-all-about-the-ball mentality to create turnovers, while the Patriots boast one of the biggest and most physical units.

Atlanta is more likely to penetrate at the snap and create disruption; the Patriots often ask their defensive linemen to play a two-gapping technique by controlling the blocker in front of them while remaining patient. New England led the NFL in scoring defense during the regular season (an average of 15.6 points per game allowed), while Atlanta ranked 27th in points allowed (25.3). One thing that helped the Falcons' defense was the fact the unit was often playing with the lead, a result of the team outscoring opponents 139-68 in the first quarter.

CALLING CARD

Falcons: Speed and physicality. When Dan Quinn left his defensive coordinator job in Seattle to become the head coach of the Falcons, his signature phrase was "fast and physical." It took a bit, but Quinn eventually established such an identity within his defense. It started with NFL sacks leader Vic Beasley Jr., who used his devastating speed off the edge to record 15.5 sacks to go along with six forced fumbles. Then rookie middle linebacker Deion Jones, one of the fastest linebackers the Falcons have had in years, put his stamp on the defense with a 90-yard interception return for a touchdown against his hometown team, the New Orleans Saints, in his first game inside the Superdome. Atlanta won that game 45-32. Jones finished the season with a team-high 106 tackles, and fellow rookie Keanu Neal, the enforcer at safety with his punishing hits, finished right behind with 105 stops. Free safety Ricardo Allen showed the range and open-field tackling to help eliminate big plays, and the cornerback tandem of Robert Alford and Jalen Collins made up for the loss of speedy Pro Bowl CB Desmond Trufant (pectoral surgery).

The Falcons' Vic Beasley led the NFL with 15.5 sacks this season. AP/Brad Penner

Patriots: Tackling. The Patriots' defense led the NFL in fewest yards allowed after the catch (4.05 average), which reflects their solid tackling. While some teams teach a style of holding up the ball carrier so others can rally to the ball and attempt to strip it, coordinator Matt Patricia focuses more on defenders tackling ball carriers to the ground. It shows at every position, including cornerback, which is often overlooked in the run-force game. Sound tackling has also contributed to one of New England's more impressive statistics: Its defense hasn't allowed a 90-yard rusher in the past 25 games, dating to 2015. Meanwhile, creating turnovers has long been a staple of the Patriots' defensive unit; after totaling just nine through the first nine games (two of which came on special teams), the group exploded for 14 over the final seven regular-season games of 2016.

MOST IMPRESSIVE GAME OR STRETCH OF GAMES

Falcons: During Atlanta's current six-game winning streak, its defense has made significant strides from the one that surrendered 27.9 points per game through the first 12 games of the regular season. Over this six-game stretch, the defense has allowed just 19.3 points per game. Playing the likes of the Rams and 49ers offered an opportunity to pad numbers, but it's hard to argue with the Falcons holding their own in playoff matchups against Aaron Rodgers and Russell Wilson. In the playoffs, the Falcons have forced four turnovers, building off the momentum from the end of the regular season. Quinn preaches "the ball" all the time, which is why the Falcons finished the regular season with a plus-11 turnover ratio, tied for fourth in the NFL.

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Patriots: Denver has traditionally been a challenging place for the Patriots to play (10-21 all time), but the defense did its part in a 16-3 win Dec. 18. Sure, it was against quarterback Trevor Siemian and an offense that doesn't qualify as lethal, but on a day when the Patriots' own offense was struggling to find its groove, the defense put the clamps down in holding the Broncos to a 2-of-12 success rate on third down while recovering one fumble and intercepting a pass. In a dominant stretch to open the second half, the defense produced five straight three-and-out drives.

THE ONE TO WATCH

Falcons: Beasley. He doesn't have a sack or a quarterback hit yet this postseason, so he's due. Of course, opposing teams are chipping him more often, knowing how dominant a pass-rusher he can be. Now it's up to Beasley to keep his focus and play with the same intensity he has all season. His likely matchup in the Super Bowl will come against Patriots right tackle Marcus Cannon. The Patriots have lost two of the three Super Bowls in which quarterback Tom Brady was sacked multiple times. Beasley had four multisack games in the regular season.

Malcolm Butler is up for the challenge of facing Julio Jones in the Super Bowl. Photo by Jim Rogash/Getty Images

Patriots: Malcolm Butler. One of the remarkable out-of-nowhere stories in the NFL, the third-year cornerback from West Alabama was determined not to rest on his laurels after his game-saving interception in the Super Bowl victory over the Seahawks two years ago. He was No. 5 on the depth chart at the time of his unforgettable goal-line pick but rose quickly to the No. 1 spot in 2015 and 2016 while becoming one of the team's most consistent and dependable players. Butler played 98.8 percent of the snaps in 2015 and 96.7 percent in 2016 and was often called upon to line up across from the opponent's top receiver.

SOMETHING YOU DIDN'T KNOW

Falcons: The Falcons established a first in starting four rookies on defense in the NFC Championship Game with Jones, Neal, linebacker De'Vondre Campbell and nickelback Brian Poole. If the lineup remains the same Feb. 5, it will mark the first time that has occurred in a Super Bowl. All four have been key to the team's resurgence, with Neal (first round), Jones (second) and Campbell (fourth) being draft picks and Poole an undrafted player. The Falcons also start three second-year players on defense in Beasley, Collins and nose tackle Grady Jarrett.

Patriots: Second-year defensive end Trey Flowers, who led the Patriots with seven sacks during the regular season, has had notable success as a pass-rusher when moving inside in obvious passing situations. His quickness and long arms have given interior offensive linemen some issues. Flowers played in only one game in his rookie season in 2015. He was buried on the depth chart and didn't provide enough special-teams value to crack the 46-man game-day roster. Bill Belichick said one of the key decisions that set Flowers up for success in 2016 was placing him on injured reserve in the final month of the 2015 season (shoulder) so he could get a head start on his rehab. Flowers, who played at Arkansas, was acquired with the 2015 fourth-round draft pick the Patriots received from Tampa Bay in exchange for guard Logan Mankins.