COSTA MESA, Calif. -- In the aftermath of a gut-wrenching wild-card playoff loss, several Los Angeles Chargers defensive players expressed a desire to keep the unit together moving into the 2023 season.

Veteran outside linebacker Joey Bosa, however, delivered a dose of reality.

“We can’t. It’s not up to us,’” Bosa said. “Obviously guys would love to be here, but there are a lot of guys who have got to get paid and it’s a business.”

The Chargers finished the 2022 season 10-7, overcoming a plethora of injuries to earn their first playoff berth in four years, but ultimately fell short of contending for a conference championship.

The Bolts ranked 25th in defensive efficiency but jumped to ninth down the stretch as they improved from allowing an average of 22.6 points per game (21st) to 15 points per game (3rd) over their last five contests.

“We played well down the stretch,” general manager Tom Telesco said after the season. “You saw what the defense can get to.”

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In a 31-30 wild-card playoff loss to the Jacksonville Jaguars, the defense proved dominant throughout the first half, forcing four turnovers. But the effort faded in the second half as quarterback Trevor Lawrence passed for four touchdowns to eliminate a 27-point deficit and move onto the divisional round.

As the Chargers look ahead, coach Brandon Staley emphasized the need to limit explosive plays, play better on the perimeter and improve tackling.

“We have to tackle better on the edges. We have to make sure we put a roof on the deep part of the field,” Staley said. “Those are going to be the areas that we really need to focus on in the offseason.”

The Chargers are currently projected to be $20.5 million over the 2023 salary cap, according to Overthecap.com, which they must be in compliance with at the start of the new league year on March 15.

“We have a lot of puzzle pieces to kind of work in this year to figure out what’s the best makeup of our team going into next year,” Telesco said. “Obviously, contracts and money are all part of it.”

Here’s the state of each defensive position group -- great, satisfactory or needs adjustment -- as they look ahead to free agency and the draft.

The line underwent a makeover last offseason, adding Sebastian Joseph-Day and Austin Johnson and experienced a significant in-season shakeup when the team waived former first-round pick Jerry Tillery in November.

This was among the most injured groups on the team -- at one point, only three healthy linemen were available to finish a Week 10 loss to the San Francisco 49ers -- with Johnson, rookie Otito Ogbonnia, Christian Covington and Joe Gaziano all landing on injured reserve throughout the year.

The Bolts allowed an average of 145.8 rushing yards per game (28th), including a league-worst 5.42 yards per carry. Building a group that can slow the run must be prioritized for another offseason.

Joseph-Day and Johnson are scheduled to return, along with Ogbonnia, providing some continuity as they prepare for a second season together.

“Our first-down defense... need a lot of improvement there,” Telesco said. “Don’t forget, it’s not like teams run the ball every first down, so there’s also passing involved there, but there has to be major improvement there.”

The Bolts should attempt to bring back Morgan Fox, who is scheduled for free agency after playing on a one-year, $1.19-million contract. Fox finished with career-high 6.5 sacks, which ranked second on the team.

The Chargers made a splash last offseason completing a blockbuster trade for Khalil Mack, which arguably formed the greatest pass-rushing duo in the NFL with Joey Bosa. That partnership, however, never materialized after Bosa was placed on injured reserve after Week 3 and missed 12 games.

Mack, coming off a season-ending foot injury, proved at age 31 that he has plenty of football remaining after he produced eight sacks and forced two fumbles despite attracting significant attention from opponents.

With Mack and Bosa, the Bolts should be set in 2023 -- so long as both remain healthy.

Depth at the position remains a need.

Kyle Van Noy provided a significant spark down the stretch as he collected a sack in five consecutive games, but the ninth-year veteran is scheduled for free agency after playing on a one-year, $2.25 million contract and it’s unlikely the budget will allow for his return.

The Bolts might be in a position where they’ll be forced to depend on the development of Chris Rumph II, a 2021 fourth-round pick, who has yet to prove himself as a consistent contributor.

Drue Tranquill anchored the group as a fourth-year pro with a team-high 144 tackles and 4.5 sacks, while serving most of the season as the defensive signal caller. However, he is scheduled for free agency and given the salary-cap constraints, it’s unlikely the 2019 fourth-round pick will return.

The Chargers will not only need to find a solution to start alongside Kenneth Murray Jr., who finished last season with 76 tackles and a sack, but must also decide whether to pick up the fifth-year option on Murray’s rookie deal.

The Chargers spent big money in free agency last year on cornerback J.C. Jackson, signing him to a five-year, $82.5 million contract.

But it remains unclear if Jackson is a fit in Staley’s scheme. He had yet to prove it in 2022 before suffering a season-ending knee injury in Week 7, and it’s unclear how long it will take Jackson to return to form after having surgery to repair a ruptured patellar tendon in his right knee.

“What he has going for him is his age and the fact that he’s in such great physical condition that he should be able to come back from this injury,” Telesco said. “It’s not an injury that we see that often.”

In Jackson’s absence, Asante Samuel Jr. commanded attention as he demonstrated continued improvement in his second season, highlighted by his three interceptions in the first half against the Jaguars.

And Michael Davis, appearing at the outset of the season as the odd-man-out, proved himself as a reliable playmaker with 15 passes defended.

Bryce Callahan, who quietly led the team with three interceptions, is scheduled for free agency and also is among those unlikely to return because of a lack of cap space. There’s no clear solution who can step into the slot.

This offseason will be significant in the development of 2022 sixth and seventh-round picks Ja’Sir Taylor and Deane Leonard.

This group will be great if it establishes a counterpart for Derwin James Jr.

Nasir Adderley, a 2019 second-round pick, is scheduled for free agency and is not expected to return after he was benched twice last season, including in the wild-card playoff.

Alohi Gilman started in Adderley’s place and performed well, but it’s unclear whether the 2020 sixth-round pick is a long-term solution.

And, like other young players going into the offseason, the development of 2022 third-round pick J.T. Woods, who recorded only one tackle in 28 defensive snaps, will be significant in his effort to contribute moving forward.