Houston — It's tough to explain just how inept the Buffalo Bills' offense was on Sunday.

The 316 total yards wasn't a terrible total, but there were so many puzzling things about the way the Bills arrived at a mediocre points in a 23-17 loss to the Texans. Quarterback EJ Manuel struggled, the play calling was curious, and according to wide receiver Mike Williams, the Bills were thrown off by what the Texans threw at them.

"They kind of caught us off guard with their defense a little bit," Williams said after the game. "I mean, no excuse, we have to adjust, but we thought they was going to play one way, they played another way. There's no excuses. We kind of adjusted after that."

Williams went on to say the Texans were playing close to the line of scrimmage with a single high safety. That's part of why Williams broke free for an 80-yard touchdown. Manuel didn't think the Texans were doing much different, though.

“I didn’t see anything different," Manuel said. "I thought the biggest difference from what we saw on film was that they played a little softer coverage. But outside of that, there wasn’t too much different.”

This is the second-straight week the Bills have mentioned being thrown off by something they saw in the defense. It's also the second-straight game the Bills have lost. Here are a few notes about the rough outing for the Bills' offense.

The Bills ran the ball once on third down

That stat alone says it all. The Buffalo Bills need to be leaning on their running game, and in the most crucial situations they weren't doing that. It's not like the Bills were constantly stuck in third-and-long, either. The Bills also converted only five of 16 third downs, including one of seven in the second half.

EJ Manuel attempted 44 passes

In the Bills' two wins this season, Manuel attempted 22 and 26 passes. In the two losses, he attempted 39 and 44. The run-pass balance wasn't there for Buffalo on Sunday, and 10 points was the largest deficit they faced all afternoon, so playing from behind can't be used as an excuse.

EJ Manuel completed 47 percent of his passes

Manuel's completion percentages have been taking a nose dive since the start of the season. In Week 1, Manuel completed 72.7 percent of his passes. That number dropped to 61.5 percent in Week 2, 59.0 in Week 3, and on Sunday Manuel completed 47.7 percent of his passes. A lot of that falls on accuracy, but Manuel wasn't the only issue.

EJ Manuel was hit 16 times

The Texans got after Manuel early and often with an aggressive pass rush. Houston had 16 quarterback hits, and J.J. Watt had nine of them. To put that in perspective, the Bills allowed only eight quarterback hits in the first three games of the season combined. There's a reason Manuel was a bit rattled after the game.

The Bills ran the ball seven times in the second half

This is the most puzzling stat of all. The Bills never trailed by more than 10 points on Sunday, and yet they attempted only seven running plays in the second half. It's not a secret that the Bills are a run-first team. Running backs C.J. Spiller and Fred Jackson looked good on Sunday, too. Why the Bills completely abandoned the running game is a bit of a head-scratcher.