History tells us that the Super Bowl usually is won by the team with the better quarterback and the better defense. You can plan on rewriting that equation this year to this simple truth: In today's game, it's all about the quarterbacks.
Three of the four have won a total of seven Super Bowl titles, and the fourth is the reigning NFL passer rating leader. Counting this weekend, the four will have 20 combined appearances in conference championship games -- 11 by Brady alone. It's the fourth appearance for Roethlisberger, third for Rodgers, second for Ryan.
And, this marks only the third time that the conference championship games feature three quarterbacks with Super Bowl rings -- Brady with his four, Roethlisberger with two and Rodgers with one.
Among other things, this means we shouldn't expect any stage fright. Except for Ryan, all three have been through the playoffs successfully, and even Ryan, whose passer rating of 117.1 dwarfed the league, could have a Super Bowl ring but for an Atlanta defensive collapse in the 2012 playoffs.
That experience ought to serve Ryan well against Rodgers and the Packers, because he learned never to take your foot off the gas at this stage. In the 2012 NFC championship game, Ryan staked the Falcons to a 17-0 lead over the 49ers six seconds into the second quarter. But a pair of third quarter turnovers and a defense that permitted three 80-yard touchdown drives turned the game in the 49ers' favor.
Ryan, Brady and Rodgers ranked 1-2-4 in the league in passer rating this year (the interloper, No. 3 Dallas' Dak Prescott, was eliminated by Rodgers' Packers last weekend). Roethlisberger ranked 11th but brings the longest winning streak to this championship weekend -- the Steelers have won nine games in a row.
The emphasis on quarterbacks is merely a reflection of how professional football has evolved over the years. A little more than four decades ago, the Miami Dolphins won back-to-back Super Bowls, the first completing an undefeated season, with quarterback Bob Griese throwing 18 passes. That's total, in the two Super Bowls. Rodgers threw 24 passes against Dallas last week. In the first half.
During the regular season, the four championship game quarterbacks threw 135 touchdown passes and 29 interceptions, a ratio of better than 4-to-1. That foursome in 1983 including Montana, Theismann and Plunkett? They threw 82 touchdown passes and 48 interceptions, a ratio of less than 2-to-1.
All four of these final four teams ranked higher in the league on offense than they did on defense, which stands the old cliche -- defense wins championship -- on its head.
The two NFC contenders, Atlanta and Green Bay, both ranked among the league's 11 worst on defense. The highest defensive ranking among the final four teams, New England's No. 8, just happened to match the worst offensive ranking among the four, Green Bay's No. 8.
It used to be rare to see a defense still playing at this stage that was not among the very best in the league, and they all had catchy nicknames -- remember the Steel Curtain, the Fearsome Foursome, the No-Name Defense, the Doomsday Defense, the Orange Crush? Now, we don't have defensive nicknames, we have defenses that just try to hold on.
Right about now, someone is going to shout, "What about Denver last year?" Yes, what about Denver last year? The Broncos were something of a throwback team, with a suffocating defense carrying a Hall of Fame quarterback at the tail end of his career. The Broncos were the exception that proves the rule.
Which brings us to the point that you were waiting for.
First, some background. Brady is 6-4 in championship games including 4-1 at home. Roethlisberger is 2-1, all at home, so this is his first championship game on the road. Rodgers is 1-1, both on the road. Ryan is 0-1, at home.
More historical facts: The average defensive ranking for a Super Bowl champion is No. 7; these four teams averaged 14th on defense. The top-ranked defense has reached the Super Bowl 11 times. This year's top-ranked NFL defense, Houston, was the only one of the top four defensive teams even to reach the playoffs.
The world seems to be anticipating a Brady-Rodgers matchup, and that's probably the sexiest possible, too. Pundits already are salivating over the prospect of Roger Goodell having to hand the Lombardi Trophy over to Brady, whom he suspended for the first four games the season because of that ridiculous Deflategate matter.
But we don't always get what we want.
Pittsburgh's running game, with Le'Veon Bell, is the best going right now. And you can throw out that regular season meeting, won by the Patriots, 27-16, because Roethlisberger did not play.
AFC pick: Steelers.
In the NFC, neither the Packers nor the Falcons have the kind of defense that figures to be able to stop the other team. That's how their October game played out, Atlanta winning, 33-32, on a last-minute touchdown; both quarterbacks had passer ratings north of 125. Look for the same thing, different result.
NFC pick: Packers.
--Ira Miller is an award-winning sportswriter who has covered the National Football League for more than five decades and is a member of the Pro Football Hall of Fame Selection Committee. He is a national columnist for The Sports Xchange.