Whatever happened to the old mantra that defense wins championships?

With more rules designed to protect offensive skill players from injury, the speed of the game only increasing and the number of elite quarterbacks continuing to rise, turnovers could be more than just a defense's most important tenet. If the air-it-out trend in the NFL keeps going, takeaways might be the defense's only hope.

Just ask Pittsburgh and Houston, two teams that have historically relied on stout defense and are giving up yards and points in huge chunks this season.

"It's a huge point of emphasis for us. ... That's a huge momentum-changer. I mean, it's just one of those things that gives everybody energy," Houston All-Pro defensive end J.J. Watt said. "We need to do it. We need to give our offense the ball on a short field. We need to make sure that we provide that spark."

The Texans are one of a handful of prime examples of the significance of the turnover in the early going this season. Through the first three weeks, they allowed only 249 yards per game, the second-lowest average in the league behind the Seattle Seahawks. But they gave up 82 points in that span, nearly one-third of which was attributable to turnovers by the offense or mistakes on special teams. With only one takeaway over those three weeks, the Texans were fortunate to have won twice. They forced two turnovers by Seattle last weekend, but lost in overtime.

"You just keep working at it and you keep stressing it, continuing to do it in practice," Texans linebacker Brian Cushing said. "Hopefully, it just transfers over to the games."

Pittsburgh has been feeling this pain even more.

The Steelers have lost their first four games and failed to force a turnover in any of them. That defense is 12th overall in the league in yards allowed, but it doesn't matter. Like the Texans, not only have the Steelers not produced enough takeaways, but the offense has had too many giveaways.

The Steelers have ranked in the top 10 in the NFL in fewest yards allowed in each of the last nine seasons, including finishing with the lowest in the league four times. But they've only been among the top 10 teams of turnovers forced once in that stretch.

"We've got to find ways to get the ball. That's what great defenses do," defensive end Brett Keisel said. "It's been one of those things for a while now we haven't been able to get turnovers. Hopefully it will change."

There's no secret the NFL has developed into a pass-driven product. More strong-armed quarterbacks are making their mark on this league than ever, and some of them have become dangerous dual threats with their read-option running plays.

There were 155 touchdown passes thrown through the first three weeks, the most ever in that span to top the previous such high of 153 in 2011. The first three weeks also brought 30 individual performances of 300 yards passing or more, including seven of 400-plus, trailing only the 34 that were registered in 2011.

Scoring is about the same. The average of combined points per game last season was 45.5, according to research by STATS. Through the first three weeks this year, the number was 45.2.

When that ball pops out or gets picked off, though, all bets are off.

"I think the biggest thing still, no matter what, is the turnover battle and the way it's hurting our football team and the way it's putting us in a bad situation," Texans coach Gary Kubiak said. "It's something we have to get back on track."

San Francisco took a step toward that last week. The 49ers had a total of one takeaway in their two losses. When they beat up on the Rams in St. Louis, they forced two turnovers to go with their five sacks.

"On this defense, we've definitely got to stop the run," cornerback Carlos Rogers said. "Stopping runs is our No. 1 thing and making a team pass the ball. Once we get back to that, getting back to creating turnovers, we'll be back to the same defense."

Want a small-sample-size success story? Try Tennessee.

The Titans were 27th in the league in yards allowed last year and minus-four in turnover differential. Through the first three games they were plus-nine, tied atop the NFL with Kansas City. They were 11th in yards.

"The old school saying, 'Offense wins games, defense wins championships,' I think that's still true," cornerback Jason McCourty said.

Keep taking away that ball and, well, he could prove himself right.


AP Sports Writers Will Graves in Pittsburgh, Janie McCauley in San Francisco, Kristie Rieken in Houston and Teresa M. Walker in Nashville, Tenn., contributed to this report.



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