Four of the five teams that gave up the fewest points during the regular season are the last four left with a shot at the Super Bowl, something that had never happened since the NFL-AFL merger nearly a half-century ago.

And three of the four toughest to gain yards against are still around, too.

Still think that all a team needs to succeed in the modern game is an elite QB? Go ahead and take a close look at Sunday’s matchups for the conference championship games.

Sure, Tom Brady (assuming his injured right hand is good to go) and the New England Patriots will be playing for the AFC title, just like they always do, but they’ll be going up against Blake Bortles and the Jacksonville Jaguars. Over in the NFC, the Philadelphia Eagles will send Nick Foles out to face the Minnesota Vikings and Case Keenum, hardly a marquee matchup between quarterbacks, and one set up by injuries to other signal-callers.

What this quartet of teams does have in common is solid defense, showing once again that while everyone is paying so much attention to one side of the ball, it’s the other that might truly matter the most. The more league rules and officiating tend to favor offenses, the more figuring out ways to slow that down is imperative.

“When you have a defense that can shut that type of firepower down,” said Brian Robison, a linebacker on the Vikings defense that ranked No. 1 in yards and points allowed, “it allows you to win ballgames.”

Minnesota gave up 15.8 points per game. Jacksonville was No. 2 at 16.8, followed by No. 4 Philadelphia’s 18.4 and No. 5 New England’s 18.5.

“There’s teams that have really good defenses that aren’t talked about,” Patriots linebacker Kyle Van Noy said. “We’re one of them.”

It’s the first time since the 1970 merger there has been that sort of defensive dominance among the NFL’s final four. The closest was at the end of the 2010 season, when teams that ranked No. 1 (Steelers), No. 2 (Packers), No. 4 (Bears) and No. 6 (Jets) in points allowed reached the conference title games.

“The most heralded guys on the field are the quarterbacks. So I would say, nine times out of 10, your detail goes into your offensive planning and things like that,” said Jacksonville’s leading tackler, Telvin Smith, who returned a fumble 50 yards for a touchdown last weekend. “Offense sells tickets, and defense wins championships. I’m happy I’m on the defensive side.”

Take a look at the regular-season rankings in various defensive categories, and you can’t miss the Jaguars. That helps explain how they made it this far with Bortles.