By Amy Lawrence

Defense wins championships. It’s a cliche for a reason. And in the NFL, recent evidence backs it up.

The Super Bowl champion Denver Broncos won their title with a brash, bold, aggressive defense and then doubled down on MVP Von Miller with a ginormous offseason contract. They were prompted to focus and invest more on the defensive side of the ball after they got embarrassed in the Super Bowl two years prior to last February. The Seattle Seahawks started THAT game with a safety, returned a Peyton Manning interception for a touchdown and pitched a shutout for almost three quarters. Linebacker Malcolm Smith earned Most Valuable Player honors in the rout. Not only have two of the last three championship game MVPs been defensive stars, but the moment to remember from Super Bowl 49 will always be Malcolm Butler picking off Russell Wilson on the goal line in the final 30 seconds to secure a Patriots victory.

The NFL is a copycat league where front offices and coaching staffs tend to imitate success. They see what’s working and try similar strategies as they search for their own winning formulas. With a month to go in the regular season, it’s wise to gauge the defensive climate in the league. A handful of teams and individual performances definitely stand out as we put Week 13 to bed.

One of the year’s most powerful and noteworthy efforts was delivered by Kansas City safety Eric Berry on Sunday in Atlanta. First, he intercepted Matt Ryan for a Chiefs touchdown near the end of the first half. He gave the ball to his mom in the stands and told her he’d be back. He was right. He also picked off Ryan’s pass attempt on a two-point conversion late in the 4th quarter to put his team in front. Berry delivered that second ball to his dad. To play a major role in the Chiefs’ 20th win in their last 24 tries would be enough. But it was also Berry’s first career game in his hometown and his first mid-season trip to Atlanta since he received chemotherapy for Hodgkin’s lymphoma two years ago this week.

The 2015 Comeback Player of the Year admitted he cried before, during and after the game. With dozens of family members and friends in attendance, Berry’s triumph transcended football. The weekend in Atlanta brought him full circle and gave NFL fans across the board a reason to stand and cheer. He wore special purple cleats designed to raise awareness about the disease he battled; but it’s the passion, drive and intensity Berry brings to the field as a cancer survivor that make him a hero.

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It should come as no surprise that Kansas City is tops in the NFL with 25 takeaways and four defensive touchdowns. Berry’s leadership and a fierce pass rush are big reasons why the Chiefs could soon be challenging for a title. With a 9-3 mark, they trail the Raiders by a single game in the AFC West. Oakland may only play defense for half of each game, but Khalil Mack is single-handedly wreaking havoc. With 10 sacks, four forced fumbles, his first career interception and first career score, the defensive end keeps opposing offenses on edge. In the same division, Miller is putting together another massive campaign after the Broncos made him the league’s highest-paid defensive player. He’s pacing the NFL with 12.5 sacks and quarterback nightmares. Denver is navigating this season the same as last: a ferocious, opportunistic defense that takes the pressure off an inconsistent offense.

The Seahawks are up to their old tricks. Kam Chancellor, Bobby Wagner, Michael Bennett, Cliff Avril, Richard Sherman and company are giving up a miserly 16.2 points per game. That average is a full point lower than the league’s next best team’s! Their latest victory was costly, though, as Pro Bowl safety Earl Thomas broke his leg against the Panthers when he collided with Chancellor over the middle. In Baltimore, the Ravens count on their D to keep them close. A breakout performance by Joe Flacco and the offense versus Miami was welcome, but it’s the defense allowing just 17.3 points per game. They also surrender the fewest number of rushing yards and total yards per game in the NFL.

The Dallas Cowboys clinched a playoff spot in Week 13, and they haven’t lost since their opener, thanks in large part to an overachieving defense. By holding teams to 19 points and just over 82 rushing yards per contest, they put Dak Prescott and Ezekiel Elliott back on the field as quickly as possible. In hot pursuit of Dallas in the NFC East, the New York Giants are seeing their high-priced defensive investments pay dividends in the second half of the season, though it’s second-year safety Landon Collins and his rookie contract leading the team in both tackles and interceptions.

Defense isn’t predicated on rhythm and timing. Success is largely tied to effort, intensity, toughness, focus, communication and desire. And defense typically travels well. As the weather turns colder and the stakes get higher, overlook the NFL’s best defenses at your own peril.

A well-traveled veteran and pioneer of sports radio and television, Amy Lawrence is the host of CBS Sports Radio’s late-night program ‘After Hours with Amy Lawrence.’ The show can be heard weekdays from 2-6am ET on the nation’s largest 24/7 major-market radio network. Follow her on Twitter @ALawRadio.