Inside the numbers: Week 4

The NFL has given us plenty of sexy, big-name quarterback rivalries over the years.

But none ever matched the fireworks of Peyton Manning vs. Tom Brady: two prolific future Hall of Fame quarterbacks who put up monster numbers and meet year after year in games that have a profound impact on the Super Bowl picture.

The Cold, Hard Football Facts deemed Manning vs. Brady the best QB rivalry in NFL history way back in 2007.It still is today.

The greatest quarterback rivalry in football history unfolds for the 13th time Sunday afternoon at Gillette Stadium when the Denver Broncos (2-2) visit the New England Patriots (2-2). Brady holds an 8-4 advantage in the previous 12 meetings (6-3 regular season; 2-1 postseason).

The winner of the regular season series between Brady's Patriots and Manning's former Colts gained home-field advantage over the other in the playoffs every single time. That's eight of the last 11 seasons, for those of you keeping score at home (2001, 2003, 2004, 2005, 2006, 2007, 2009 and 2010).

The two have also squared off three times in the postseason, in 2003, 2004 and 2006. The winner of that game went on to win the Super Bowl all three years. Manning sparked the greatest comeback in conference championship game history to steal a win over the Patriots in the 2006 AFC title tilt.

In other words, Manning and Brady meet far more often than most great QB rivalries -- and they meet in Big Games of Big Consequence.

The sheer statistical dominance of each quarterback adds yet another layer to the rivalry. Both Brady and Manning are among the all-time leaders in every major career and single-season passing record.

And here's the best part for football fans: it seems these aging gunslingers are not quite ready to hand over their badges to the NFL's young guns.

Instead, both quarterbacks head into their Week 5 showdown at the top of their game: Denver and New England boast the league's best offenses right now when we measure them relative to the quality of the defenses each team has faced.

Brady has led the Patriots to a league-best 134 points this year, including a 45-point explosion in the second half alone at Buffalo on Sunday. Manning's Broncos have scored 114 points, including a 37-6 win Sunday against Oakland. Denver had topped that scoring total just twice in its previous 41 games.

But here's where Manning's Broncos actually have the advantage.

The Cold, Hard Football Facts size up each team on what we call the Relativity Index. It measures how each team performs, both offensively and defensively, relative to the quality of their opposition.

Manning's Broncos have averaged 28.5 PPG this year. But they've done it against teams that have surrendered just 18.2 PPG in other games.

So the Denver offense is actually +10.3 PPG better than the defenses they have faced. That's the best mark in the league.

Brady's Patriots have scored a league-best 33.5 PPG this year. And they've done it against teams that have surrendered 24.3 PPG in their other games.

So the New England offense is actually +9.2 PPG better than the defenses they have faced. That's second only to Denver.

The Relativity Index is much more than just a trivial statistical exercise. It is the most accurate predictor of victory in football.

Teams that were better on the Relativity Index won 67.4 percent of all NFL games last year, according to the Predictive Rate of Victory table we use at CHFF Insider. No stat does a better job of predicting winners and losers all by its lonesome.

The indicator grows better at predicting winners as we get later in the year and have more data under our belts. But it was 10-5 predicting winners last week.

That's good news for Denver, which is No. 2 overall right now on the Relativity Index. New England is No. 6 (more on those standings below).

Brady and Manning, by the way, enter their Week 5 showdown virtually neck and neck in their individual statistical showdown this season:

Brady: 101 of 154, 65.6 percent, 1,227 yards, 8.0 YPA, 7 TD, 1 INT, 102.4 ratingManning: 99 of 153, 64.7 percent, 1,162 yards, 7.6 YPA, 8 TD, 3 INT, 96.9 rating

We don't know who will have the advantage on Sunday. But we do know this: whoever does gain that advantage on Sunday will gain the inside track on the 2012 playoff race.

Either Tom Brady's Patriots or Peyton Manning's Broncos will be 3-2 by early Sunday evening. But neither team appears equipped to stop the mighty Houston Texans, who are on an early pace to be one of the most dominant teams in modern NFL history.

Houston was the Cold, Hard Football Facts preseason pick to win the Super Bowl. And so far the 4-0 Texans have exceeded our wildest expectations.

They dominate the NFL in two key indicators of success.

The first is the Relativity Index, which we discussed above. Denver and New England are No. 1 in offensive relativity. But if we look at both sides of the ball, Houston is the most dominant team in football, even when we take into account the quality of the opposition.

Here is the Top 10 on the Relativity Index entering Week 5:

1. Houston -- +16.8 points (+6.9 on offense; +9.9 on defense)2. Denver -- +15.5 (+10.3; +5.2)3. Atlanta -- +14.6 (+8.1; +6.5)4. Arizona -- +12.7 (+3.4; +9.3)5. Baltimore -- +12.7 (+8.3; +4.4)6. New England -- +12.5 (+9.2; +3.3)7. San Francisco -- +11.3 (+3.3; +8.0)8. Chicago -- +8.9 (+7.4; +1.5)9. Green Bay -- +7.3 (+1.6; +5.7)10. Seattle -- +3.9 (-3.4; +7.3)

Houston is also dominant in our Quality Stats Power Rankings. This is our measure of the average performance across the board in all of our Quality Stats, each of which has a direct correlation to winning football games. Teams that top the Quality Stats Power Rankings have a habit of reaching Super Bowls at worst.

The Texans rank No. 2.8 on average in each of our indicators. That number represents incredible top to bottom strength in all phases of the game. They rank no worse than No. 6 in any individual indicator, Real Passing Yards Per Attempt (7.36 YPA).

We've rarely seen a team so good in so many indicators. For a little perspective, the 16-0 2007 Patriots were the most dominant NFL team since World War II, and the only club in NFL history to score 300 more points than it surrendered (589-274).

Those Patriots ranked, on average, 3.4 across the board in our 2007 Quality Stats Power Rankings.

Houston (through four games) is slightly stronger than the wire-to-wire 2007 Patriots. But as we saw, those Patriots started red hot and couldn't keep the momentum going, ultimately faltering in the Super Bowl.

The Texans right now are on pace to score 504 points and surrender 224. That 280-point differential would be third in the Super Bowl Era, behind the 2007 Patriots (+315) and 1999 Rams (+284).

Week 4 provided another mixed bag for the collection of rookie quarterbacks that we track right here each week.

Robert Griffin III's Redskins edged out the Buccaneers in Tampa, 24-22. Brandon Weeden's winless Browns fell just one play short of toppling the mighty Ravens in Baltimore, losing 23-16. Russell Wilson's bi-polar Seahawks, so good at home and so bad on the road, lost at St. Louis, 19-13. Ryan Tannehill's Dolphins put up a game effort at undefeated Arizona, before falling 24-21 in overtime. Andrew Luck and the Colts had the week off.

RGIII easily maintained his edge on the field, and remains one of the NFL's most efficient quarterbacks with a 103.2 rating (fourth league-wide).

He failed to throw a touchdown for the first time this year against the Bucs, but did run for a 5-yard score. More importantly, he led a drive from his own 20 to the Tampa 24 to set up Billy Cundiff's game-winning field goal with just three seconds to play.

Luck gained on the field by sitting down. He entered his bye week third among the rookie quarterbacks in passing efficiency behind RGIII and Wilson. But the Seahawks QB took a big step back with three picks at St. Louis, after throwing just one in his first three games.

Here's the rookie QB leaderboard through Week 4.