A weekly look at what the Buffalo Bills must fix:

In Week 2, the Bills had issues running the ball in the red zone. In Week 3, they had issues running the ball just about anywhere on the field.

When the Bills begin back-to-back road trips by traveling to face the Houston Texans this weekend, they can't have the same grief about their ground game. It will need to improve.

On the positive end, the Bills gained 2.18 yards after contact per rush, the NFL's fourth-highest rate in Week 3. They also gained first downs on 27.3 percent of their rushing attempts, which ranked ninth last weekend.

But they struggled on runs up the middle. On plays with more than 3 yards to gain for a first down, eight runs up the middle gained an average of 3 yards, ranking 20th.

C.J. Spiller's problems were the most pronounced. He gained 25 yards on 10 carries, including two runs for negative yardage -- both up the middle. On his first run for a loss, the Chargers blitzed safety Eric Weddle off the left edge and Spiller couldn't shake him loose in the backfield.

Spiller had a similar issue on a well-designed first-and-10 run in the third quarter. The Bills brought Marquise Goodwin in from the outside on a "jet sweep" style motion but ran Spiller up the middle. The misdirection froze an edge defender and the offensive line controlled the line of scrimmage. However, Weddle came in from the secondary and wrapped up Spiller for only a 2-yard gain.

If that same meeting takes place in the open field, Spiller probably wins with his elusiveness. The Bills' goal, then, should be to put Spiller more in space. Flare passes, screens and using Spiller as an outside receiver give him an opportunity to beat defenders that he wouldn't normally elude in the tight confines of the tackle box.