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FOXBOROUGH — Bill Belichick always wants his team playing at its best toward the end of the season.
Once the calendar turns to November, the coaching staff has a far better grasp on what does and doesn’t work, and what are the strengths and weaknesses of the team. And players gain confidence from improving as a unit on a week-to-week basis.
Before their loss to the 49ers in Week 15, the Patriots had won 21 straight games in the second half of their schedule, proof that Belichick has been able to get his team heading in a positive direction as the games remaining get fewer and fewer.
This season, the starkest change has been on defense.
Tom Brady has long proven he can move the offense no matter who is on the field with him, be it the rag-tag bunch of receivers he had in 2006, the dream team of receivers he had in 2007, or the current crop of skill players, a mix of wideouts and dangerous tight ends.
But the other side of the ball has been an Achilles’ heel for New England in recent years, as the defensive players who had led the charge in the 2000s moved on through retirement or trades and younger players were brought in.
Though Belichick had the defense playing well enough toward the end of the 2011 season that the Patriots were able to get to the Super Bowl, there were still problems as this season opened, particularly in the secondary.
Allowing long receptions was a regular occurrence, and the Patriots had trouble getting off the field on third down — a major sin. But over the last six games of the season, the defense showed a marked improvement in several important categories.
The more significant change was the addition of cornerback Aqib Talib. Talib’s arrival, via a trade with Tampa Bay Nov. 1, allowed other players to be in their proper positions in the secondary, and gave the front seven the freedom to play more aggressively.
With Talib, Kyle Arrington was kicked inside and Devin McCourty was able to stay at safety, where he is much stronger individually and can be quarterback of the secondary.
Over the first 10 games of the season, the Patriots allowed opponents to convert 43 percent of third-down chances (52 of 121), but over the last six games that percentage fell to 30.4 (24 of 79).
The number of 20-plus-yard completions for opponents fell from 4.7 per game to 3.33, and 40-plus-yard completions virtually disappeared: New England has allowed just one since the Week 11 game with the Colts, 53 yards off a screen pass in Week 16 in Jacksonville. Over the first 10 games, the Patriots allowed seven completions of 40 or more yards.
The Patriots have also clamped down in the red zone, and in the statistic Belichick says is the only one that matters, are allowing fewer points: an average of 22.5 points through the first 10 games and 17.6 since.
That includes the 41 points San Francisco scored in Week 15. The 49ers scored five touchdowns that Sunday night, but the Patriots’ other five opponents over the last six games had five total.
By comparison, while the Texans have repeatedly downplayed the idea that they are struggling on offense, the numbers show otherwise. In the areas New England’s defense has improved, Houston’s offense has taken a step backward.
Coming into their game with the Patriots Dec. 10, the Texans were averaging 29.3 points.
Since then, a five-game stretch including their wild-card win over the Bengals, that number has plummeted to 16.8.
The drop has a direct correlation to their sudden problems in the red zone: The Texans have scored touchdowns on only five of their last 15 trips inside the 20-yard line, compared with 28 of 46 (60.9 percent) over their first 12 games.
Quarterback Matt Schaub has struggled, throwing just one touchdown pass dating to the second quarter of the Dec. 2 win at Tennessee. Since throwing for two touchdowns in the opening quarter against the Titans, Schaub’s only scoring pass came against the Colts Dec. 16. He also has been intercepted four times in the last five games.
One of the contributing factors may be the offensive line. Schaub was sacked 15 times over the first 12 games, and 12 times in the last five.
The Texans were without right tackle Derek Newton when they played the Patriots the first time, but he returned to the starting lineup a week later. They have had the same starting five on the offensive line since.
It’s tough to argue Belichick’s belief that teams should get better as the season grinds on, and his defense has done that. Houston’s defense has been a strength all season, but the offense looks to be heading in the wrong direction at the worst time.