In September and October, the New England Patriots were unstoppable.

After beating Miami on Oct. 29 to improve to 7-0, they were averaging 35.6 points per game, tops in the NFL. Tom Brady was completing nearly 69 percent of his passes and had thrown 20 touchdown passes with just one interception.

The Patriots won their next three games but have since dropped two in a row, to Denver and Philadelphia.

For the first time since 2012, they take a losing streak into a game when they face the Houston Texans at NRG Stadium on Sunday evening. Their offense, particularly their quarterback, has taken a beating lately and needs to rebound against a defense that is statistically one of the NFL’s best against the pass.

The Patriots haven’t lost three in a row since 2002. It won’t be easy to stop the skid.

The defense has been fairly steady this season. The Patriots allowed 19 points per game through October and 22.8 during the five games since. They struggled a little more against the run the last two weeks, but a lot of that had to do with the absence of injured linebacker Dont’a Hightower.

The problems on offense lately have been far more glaring. Over the last five weeks, the Patriots are averaging 25.2 points – a 10-point drop in production from the first seven games.

There are myriad reasons for the offense’s struggles – injuries to Dion Lewis, Julian Edelman, Rob Gronkowski and Danny Amendola, poor offensive line play, the lack of a running game, dropped passes.

But Brady says there’s a simple way to correct all those issues: “We’ve just got to execute better. It hasn’t been good enough the last two weeks.”

Brady is getting hit more often lately, and while he said Wednesday that he felt as “fresh as lettuce,” the hits can’t continue. After all, even lettuce wilts.

He has been sacked eight times and hit another 32 times in the last three games, including four sacks and 13 hits in last Sunday’s stunning 35-28 home loss to Philadelphia. That’s the most of any quarterback in the NFL over that stretch. Brady had been hit only 42 times in the first nine games.

There are a couple reasons for this. Early in the year, when he had his playmakers healthy, Brady was getting the ball out of his hands very quickly. Teams weren’t able to get near him.

Now, minus his main targets – Edelman and Gronkowski – the receivers are having difficulty getting free of defensive backs. That’s causing Brady to hold the ball longer. And the offensive line, which has had its share of injuries all season, can only hold up for so long. Now it’s facing a Houston defense that has 30 sacks and features the most dangerous defensive player in the league in end J.J. Watt, broken hand or no broken hand.

“Ideally you’d always like to get the ball out on time in the pass game,” said Brady. “I think whether it’s some things we’ve done schematically or the opposing team has done schematically against us has forced us to hold the ball a little bit longer. I wish we would just be able to stay in rhythm.

“Judging by the results, I need to get the ball out quicker.”

But even that doesn’t necessarily mean the play will be successful these days. Minus Edelman and Gronkowski, Brady’s completion percentage has dropped rapidly. Over the last three games, he completed only 52.6 percent of his passes (72 of 137). He had been completing 68.6 percent through the first eight weeks of the season.

What’s happened? Dropped passes.

According to statistics from the NFL Network’s Evan Lazar, the Patriots have dropped 26 passes this season – second to Houston. But dropped passes are difficult to determine. Another stats service has them with 41 drops this season. According to the NFL’s NextGen Stats, Brady has had 11 more dropped passes than any other quarterback.

Regardless, the drops are happening. Against Philadelphia, Brandon LaFell, Amendola and Keshawn Martin all dropped passes on the final drive, dooming New England’s comeback.

LaFell has struggled since returning from an injury on Oct. 25. Brady has targeted him 56 times. He has caught only 25, or 44.6 percent of the passes thrown his way. According to SportingCharts, he has four drops, or a 7.1 percent drop rate. Only Edelman, who has eight drops on the year, is higher at 9.1 percent.

Brady insists he still has confidence in all his receivers, but as Coach Bill Belichick said, “in the end, if the player is not a dependable catcher, I don’t think he’s going to be involved much in the passing game.”

The Patriots could take some pressure off the passing game by running more. But New England is ranked 28th in the NFL with just 88.5 rushing yards per game. The Patriots have rushed for over 100 yards just four times this year. And they have just one individual 100-yard rusher, LeGarrette Blount, with 129 in a 27-10 win over Washington on Nov. 8.

That’s forced Brady to throw an average of 42 passes per game – nearly eight higher than his career average of 34.7.

Again, the lack of a consistent offensive line has likely hurt the running game. The Patriots began the season without their starting center, Bryan Stork, then lost left tackle Nate Solder to a season-ending injury on Oct. 11. Tackles Sebastian Vollmer and Marcus Cannon have also missed games because of injuries, and rookie guards Shaq Mason, Tre’ Jackson and center David Andrews have played big roles.

But the last two weeks, Stork has been the center. Vollmer and Cannon are settled at the tackles, with Josh Kline at one guard. Mason and Jackson rotate at the other guard, with Cameron Fleming seeing time as well. That group needs to play better in these final four games, especially with a first-round playoff bye at stake.

Typically, the Patriots aren’t panicking.

“At this point in the season, we’ve all got (to) do a little bit more to play better,” said safety Devin McCourty. “I think we’re like any other team. When you come off two losses, you understand you have to execute better and play better football, so our focus is on that.”