link to story plus charts of progress http://sportsillustrated.cnn.com/2011/writers/kerry_byrne/11/09/texans.defense/ The Houston Texans had been riddled since their 2002 inception with a persistent statistical pandemic they just couldn't shake. Year after year Houston's weak, sickly defense simply could not stop opposing passers. And if you can't stop opposing passers, you can't win games in the NFL -- no matter how many stars you have on offense. Persistently porous pass defense is the biggest reason Houston, entering the 2010 season, had the worst winning percentage of any franchise in the NFL (55-89; .382). And that incapability bottomed out last season, when Houston fielded one of the worst pass defenses in NFL history. The 2010 Texans posted a 100.5 Defensive Passer Rating -- dead last among all 32 NFL teams and one of just 10 teams in history with a DPR worse than 100. Put another way, opposing passers posted a cumulative 100.5 passer rating against Houston -- about what All-World QB Drew Brees, the second highest-rated passer in the NFL, has posted here in 2011 (100.6). If you're looking for the reason the Texans went 6-10 despite a star-studded offense, there it is right there. Enter defensive coordinator Wade Phillips, hired in the offseason to reinvent the habitually inept Houston defense. Phillips was booted out of Dallas midseason last year as the disgraced head coach of an 1-7 team. But his record as a coordinator is sparkling and, if the trends at midseason hold true, the 2011 season will go down as his best job yet. In fact, the Texans suddenly have a defense built to win in the playoffs: No. 2 in the NFL with a Super Bowl-caliber 66.9 Defensive Passer Rating. Only the Jets are better. The sudden and incredible upturn of Houston's pass defense under Phillips is the greatest statistical storyline of the season this side of San Francisco. Houston's Long, Sad History Of Pass Defense The Cold, Hard Football Facts use Defensive Passer Rating to measure pass defenses because it is a Quality Stat -- an indicator that has a direct correlation to winning football games. We wrote about the historical importance of Defensive Passer Rating here on SI.com back in January, right before Super Bowl XLIV. Super Bowl champ Green Bay was No. 1 in DPR; AFC champ Pittsburgh was No. 2 -- title-contender trends consistent throughout history. Teams that post stingy Defensive Passer Ratings compete for championships -- regardless of how many yards they allow. In fact, yards allowed are a completely useless measure of pass defense. If somebody tries to rank pass defenses based upon yards allowed, turn the channel, turn the page or turn to a new website. They're wasting your time. The 2009 Saints are the most notable recent example of a team misjudged by most experts: they were No. 26 in passing yards allowed. Therefore, many analysts thought they were vulnerable against Peyton Manning and the Colts in Super Bowl XLIV. But analysts were looking at the wrong number. The Cold, Hard Football Facts were quick to note that the 2009 Saints were No. 3 in Defensive Passer Rating -- one of the three best teams in football at frustrating opposing passers. It's the main reason we were confident of a Saints upset over the Colts. That underrated pass defense came up huge in the big game: New Orleans Tracy Porter sealed the victory with a pick-six off of Manning. It was a predictable outcome if you looked at the right indicators. Defensive Passer Rating, in short, consistently identifies champions. And that's very good news for Phillips and the Texans. Houston suddenly has a championship-caliber pass defense here in 2011 -- light years ahead of the porous units the team fielded from 2002 to 2010. Here's a look at the history of the Texans through the critical prism of Defensive Passer Rating. Texans' Defensive Passer Rating through the years Year DPR Rank Record 2002 82.1 19th 4-12 2003 86.2 26th 5-11 2004 88.7 21st 7-9 2005 100.0 31st 2-14 2006 91.6 30th 6-10 2007 93.6 30th 8-8 2008 92.3 26th 8-8 2009 83.2 14th 9-7 2010 100.5 32nd 6-10 2011 66.9 2nd 6-3 It's no coincidence that the Texans fielded their highest-ranked Defensive Passer Rating in 2009, the only year in which the organization finished with a winning record. Otherwise, the record is gruesome. Put it this way: only 10 teams in history produced a Defensive Passer Rating of 100.0 or worse -- and two of those belonged to the Texans in their first nine seasons. It's shocking, actually. Year after year, the Texans devoted incredible resources to young studs on defense, including Mario Williams, the No. 1 overall pick in the 2006 draft, and not one but two Defensive Rookies of the Year: DeMeco Ryans (2006) and Brian Cushing (2009). Despite this apparent abundance of young talent, the Texans defense was consistently porous and was shredded by opposing quarterbacks year after year. In fact, if anything, the trend was downward: Houston fielded its best pass defense in its debut season of 2002 (82.1 DPR). Houston fielded its worst pass defense in its most recent season of 2010 (100.5 DPR). But that unit that aspired to be a sieve in 2010 is suddenly a shutdown pass defense here in 2011. Houston fans should be downright giddy when they look at the team's 66.9 Defensive Passer Rating. That number alone puts a team that has never reached the playoffs smack-dab in the middle of the AFC title conversation. A little history: The average NFL champion has posted a 55.1 Defensive Passer Rating and nearly half of all NFL champions since 1940 (33) have finished No. 1 or No. 2 in the indicator. Houston is currently No. 2. And a little statistical karma: The average NFL champion here in the pass-happy Live Ball Era (1978-present) has posted a 66.4 Defensive Passer Rating, a dead statistical heat with the 2011 Texans (66.9). Bottom line: If you stifle opposing passers, you compete for championships. And here in 2011, for the first time in their history, the Texans are stifling opposing passers. Houston's Improvements Everywhere It Counts Defensive Passer Rating is Houston's most notably improved indicator, because it has such a long and proven correlation to victory and because the Texans were historically inept in that indicator last season. But Houston's improvements under Phillips are stunning by any measure. Here's how the Texans stack up last season and this season in commonly used measures of defense, as well as in many of our Quality Stats. Texans' Defensive Improvements 2010 2011 Total Defense 30th 1st Scoring Defense 29th 3rd Defensive Hog Index 24th 2nd Rush YPA Against 11th 11th Negative Pass Play% 27th 5th Third-Down Defense 23rd 4th Opp. Completion% 27th 1st Defensive Passing YPA 31st 3rd Defensive Real QB Rating 31st 3rd Defensive Passer Rating 32nd 2nd Wow! It's hard not to be impressed. Phillips was hired in January and had little interaction with his players thanks to an ugly labor dispute that did not end until August. But even with those handicaps, his team's habitually inept defense has already improved dramatically everywhere it counts in the space of nine games. By the way, there's only one indicator on the list in which the Texans have not improved: their run defense last year was just as good as their run defense this year. But that fact only serves to confirm a long-held Cold, Hard Football Facts maxim: winning in the NFL is ALL about the passing game -- it's all about passing the ball well on offense, and stifling opposing passers on defense. Phillips apparently knows this maxim, too. The Texans suddenly have a championship-caliber defense not because they're particularly stout against the run, but because their pass defense has undergone a dramatic transformation in the space of just nine games with Phillips as coordinator.