JACKSONVILLE, Fla. -- There's going to be an incredible collection of defensive talent on the field when the Houston Texans play the Jacksonville Jaguars on Sunday at 1 p.m. ET (CBS).

There will be 11 players who have made at least one Pro Bowl and eight who have earned first- or second-team All-Pro honors. The Jaguars' defense has four All-Pros -- including first-teamers Jalen Ramsey and Calais Campbell -- and eight Pro Bowlers. The Texans have three All-Pros and three Pro Bowlers, led by three-time Associated Press Defensive Player of the Year J.J. Watt.

Despite all that talent, both defenses have struggled at times this season. The Texans gave up an average of 27 points per game through the first four weeks but have allowed just 29 points the past two games. For the Jaguars, it has been the opposite: The defense gave up 63 points and 49 first downs in losses to Kansas City and Dallas after holding opponents to 14 points per game the first four weeks.

Texans reporter Sarah Barshop and Jaguars reporter Michael DiRocco break down what has gone wrong, who can help fix things and the next star on each defense:

What has each defense looked like so far?

Barshop: The Texans' defense has been much improved its past two games. The unit gave up just 16 points (in overtime) to the Cowboys in Week 5 and 13 to the Bills on Sunday.

After those first four games, safety Tyrann Mathieu said he thought the defense needed to be more consistent because "even when guys are getting to the quarterback, us on the back end, we can't seem to help those guys."

The secondary has since done a better job of complementing the excellent pass rush of Watt and Jadeveon Clowney. The Texans have struggled at times in getting off the field on third down, allowing opponents to convert 40.9 percent of third downs (16th in the NFL).

The Texans lacked a playmaker in the secondary last season but have seen improvement in that area thanks to contributions from Mathieu and versatile Kareem Jackson.

Houston will need to continue to force turnovers -- as it did against the Bills -- to get back to being an elite defense.

DiRocco: On paper, the Jaguars have a top-10 defense: second in yards per game, first in passing yards, 22nd in rushing, fifth in third-down conversions, 10th in red zone and ninth in scoring.

What's missing, though, is the big plays. What made the Jaguars' defense so dominant in 2017 was pressure and turnovers. They were second in the league in turnovers (33), sacks (55) and pressure rate (the percentage of dropbacks when a QB was sacked, under duress or hit). They lead the league in pressure rate this season (35.3 percent), but they aren't getting quarterbacks down: Their 14 sacks rank in the middle of the pack in the NFL.

The biggest problem is they've forced just five turnovers (second-fewest in the NFL): two fumbles and three interceptions. Fewer turnovers mean fewer chances to score, too. The defense scored seven touchdowns last season. This season, they've scored just one: Myles Jack's interception return in the season opener.

Which player has to step up?

Barshop: Cornerback Johnathan Joseph. Although the Texans have had a lot of success up front, thanks to the resurgence of Watt, it is the secondary that has needed to show improvement early in the season. Houston has lost three cornerbacks to injury in the regular season -- Kevin Johnson (concussion) and Kayvon Webster (quad) are on injured reserve, and Aaron Colvin is out indefinitely with an ankle injury -- so it has been up to Joseph to anchor a unit that has frequently given up big plays.

The veteran corner took a big step forward against the Bills on Sunday. He was targeted 10 times in coverage, according to Pro Football Focus. He allowed just four catches for 51 yards and returned an interception for the game-winning touchdown.

DiRocco: This is sort of cheating, but they all do.

The biggest problem the defense has had -- especially, lately -- is miscommunication.

Safety Tashaun Gipson said the issues are when the Jaguars are in zone coverage. Responsibilities differ based on routes, formations and keys, and players are getting mixed up. There were several times against the Cowboys, for example, when a safety or linebacker went the wrong way, or a cornerback bit on a route that wasn't his responsibility. Sometimes the adjustments aren't communicated quickly enough -- or at all -- in the seconds before the snap.

It's much simpler in man coverage, but that gives mobile quarterbacks a lot more space if they break the pocket. Players are running with receivers with their backs to the quarterback, so they can't see him getting outside, which often results in scrambles for first downs. That will be an issue again Sunday against Deshaun Watson.

It isn't just in the secondary. Coach Doug Marrone said there have been issues along the defensive line as well. He also placed blame on the coaching staff, himself included, for likely overloading the players with information. Things will be pared down this week.

Which player will be the next Pro Bowler?

Barshop: Nose tackle D.J. Reader. The 2016 fifth-round pick has been a force in the middle of a talented defensive line, and he has been praised repeatedly by the coaching staff and Watt for the way "he wins at the line of scrimmage."

Defensive coordinator Romeo Crennel said Reader "can win one-on-one, and then when he does get doubled, he's able to stay at the line of scrimmage and not get pushed off the line." That allows the linebackers to make plays. Reader has two sacks this season, and he could one day join Watt and Clowney at the Pro Bowl.

DiRocco: Numerous teammates believe Jack is going to be a star in the league.

It's Jack's speed at 244 pounds, which had most draft analysts listing him as one of the most talented players in the 2016 draft, that makes him special. He's able to run with backs, tight ends and some receivers in coverage and also take on offensive linemen. He's able to run down plays on either sideline, too.

However, Jack needs to start making more game-changing plays the way he did in the postseason if he is indeed going to become elite. He returned a deflected pass for a touchdown in the season opener but hasn't made a big play in the five games since.