HOUSTON -- Houston Texans coordinator Romeo Crennel isn't happy with his defense's recent funk.

During their nine-game win streak, the Texans allowed just 17.9 points per game. In the past three games, however, Houston has given up 26.0 points per game, including last week's 32-30 loss to the Eagles, which was just the second time all season that the Texans gave up 30 points.

"It hasn't been as good as we'd like to be," Crennel said. "We've been making some mistakes that are costing us yardage -- and in some cases, games -- we've got to tighten it up ... We've been seeing how we can get back to what we were doing after the three-game losing streak. That's been the focus of this group, and we'll have to wait until Sunday to see if it pays off."

Houston's magic number this season seems to be 24. When opponents put up 24 points, Houston is 1-4. When the Texans keep opponents under 24 points, they're 9-1. In losing two of their past three, the Texans allowed 24 points or more in both games.

Linebacker Whitney Mercilus said the recent struggles come down to small mistakes on a handful of plays.

"We just shot ourselves in the foot," Mercilus said. "Critical mistakes, communication, tackling, stuff like that that we did ourselves and gave up a few plays. We've got to correct that going into this week and also the postseason.

Defensive end J.J. Watt echoed Mercilus' sentiment that there have been a few lapses in attention to detail and execution.

"You have to focus in on your keys, take care of your assignment, try and stop the run, try and get after the passer," Watt said. "All of the normal stuff you have to do as a defensive player. It just comes down to executing it. Everybody around the league knows what you have to do. It comes down to will you do it or not, and we just have to make sure that we do it."

Cornerback Aaron Colvin said the secondary has given up big plays in the passing game that have been costly at times. The secondary dealt with a slew of injuries last week in Philadelphia, including to cornerbacks Johnathan Joseph and Kareem Jackson and safeties Andre Hal and Justin Reid.

"We need to challenge more," Colvin said. "We need to lock in and focus more and communicate better. It's a combination of everybody."

Although the pass defense has been inconsistent, the rush defense has remained among the NFL's best. Houston has allowed 86.2 rushing yards per game this season, fourth in the league, and a league-best 3.5 yards per carry.

The Texans held the Eagles to 57 rushing yards on 22 carries (2.6 YPC), marking the third straight game in which Houston held its opponent under 3.0 YPC and the fifth time overall in 2018, tying a franchise record set in 2009.

"We've got some great guys on the D-line who can really fill up those gaps who may not get a ton of credit, but they deserve it," Watt said. "We've got great 'backers behind us who can fill in the gaps. We take pride in it. We go out there, and we know that it's a key to our success, so we take pride in it. It's not always the most fun job, but we try and do it the best we can."

The Texans (10-5) have already earned a playoff berth, and a win against the Jaguars (5-10) to close out the regular season on Sunday (1 p.m. ET, CBS) would secure the AFC South division title outright. Houston would be the first team since the 1992 San Diego Chargers to begin a season 0-3 and win a division title.

"We've done a lot of good things over the course of those games since we were 0-3, but we have to make sure we do what we need to do to make sure that doesn't all go to waste," Watt said. "All the work that we put in over the last couple of months, we have to make sure that we make all of that work count."