A weekly look at what areas the Houston Texans must improve.

The most glaring issue for the Texans against the Buffalo Bills, playing without a fully healthy Arian Foster, was their trouble running the ball.

Their 37 rushing yards marked the second-lowest total in the league during Week 4. Their 1.54 yards per carry was the lowest. They were the only team with negative rushing yards before contact (minus-2), which might indicate issues with blocking. The Texans ranked third to last in first downs per rush attempt, getting a first down only 8.3 percent of the time. Houston ran the ball 15 times on first down and gained only 12 yards.

By comparison, the league averages in Week 4 were 4.22 yards per carry, 74 rushing yards before contact, and 4.42 yards per carry on first downs.

They were playing an excellent run defense spearheaded by one of the best defensive fronts in football, featuring Mario Williams, Kyle Williams, Marcell Dareus and Jerry Hughes. Dareus had three tackles for loss.

Foster admitted after the game that he wasn't feeling 100 percent healthy. The Texans knew that going in, and they gave him only eight carries, using him more successfully as a receiver. He was limited all week with what was listed as a hamstring injury.

This is their identity, though. Being able to control the game on the ground wasn't necessary against the Bills because the Texans' defense was able to so thoroughly discombobulate quarterback EJ Manuel, who was benched a day later. Moving forward, though, it's an important part of who the Texans are.