The Jets the past two seasons have risen into the stratosphere among NFL defenses under the guidance of head coach Robert Saleh and coordinator Jeff Ulbrich. But that doesn't mean they don't have to come up for some air and fill some needs as they enter the unrestricted free agency signing period.

The Green & White were in fact among the top five teams in any number of defensive categories in 2023. Most impressive: their No. 1 ranking in allowing opponents 4.57 yards/play. The last time they were No. 1 in that category was way back in 2009, Rex Ryan's first season at the helm.

But as the Jets and their fans know, the defense can use some shoring up. The run group ranked 25th in rush yards/game allowed and could lose three of its own veterans in free agency, while the safety position could similarly be hit FA departures.

Here is an overview of the Jets' defensive needs and the top free agents available at each level of the defense when the signing period starts March 13.

DEFENSIVE LINE

Much rests on the Jets linemen's shoulders. As the primary four-man pass-rushing unit, the DL supplied an astounding 43 of the unit's 46 sacks. Then with the linebackers, the DL is counted on to plug the running lanes. The Jets weren't horrible in run defense, especially in ranking No. 11 in yards/rush allowed and a middling 10 runs of 25-plus yards given up, but those figures weren't to the group's liking. On top of that, Al Woods, Quinton Jefferson and Solomon Thomas, all key players in the DL's interior rotation, can become free agents themselves.

DT Chris Jones (Chiefs) — Jones, with 10.5 sacks last year and 75.5 in his eight KC seasons, isn't likely to be available since Chiefs GM Brett Veach has said, "That's certainly a guy we want back and love and want to see him finishing his career in Kansas City." And the Chiefs retained the right to tag Jones this year — at a reported $32 million — after Jones signed his one-year deal one game into last season so if he gets to free agency, it will cost another team a boatload of money to lure him away from the champs.

DT Christian Wilkins (Dolphins) — Wilkins, on the other hand, is not expected to be tagged by Miami and could hit the open market, where multiple suitors would be lined up. Might the Jets try to outbid the Cardinals and Bears to get Wilkins (2.5 sacks vs. the Jets in last year's two games) away from the Dolphins and into their mix? Wilkins leads the NFL's D-linemen in total tackles the past three seasons, is third in stuffs in that span, and has been a cog in the Miami machine that's been a top-10 run defense especially in 2022-23.

DT Fletcher Cox (Eagles) — Cox has been an Eagle forever (since his rookie year in 2012) and is a six-time Pro Bowler. He hasn't made a PB since 2020, his production has slowed, and he turns 34 in December, all of which could be interrelated. But as a second-tier UFA fitting into a team's interior, he's still productive.

LINEBACKERS

It's not a deep LB free agency class, which is good for the Jets, who seem set at LB. C.J. Mosley, physical and spiritual leader of the defense and good for 150 tackles a season, is back for another season, along with Quincy Williams, who emerged even further in '23 to be named first-team All-Pro. Jamien Sherwood at the other OLB spot saw his most action in his third Jets season. And Zaire Barnes will get a chance to flash in Year 2 after playing very little as a fifth-round rookie.

LB Patrick Queen (Ravens) — Queen arrived in Baltimore in 2020, the year after Mosley left the Ravens for the Jets. In four seasons he's never missed a start, has averaged more than 110 tackles a season, and creates turnovers. He's been described as "high-risk, high-reward" and he'll carry a high pricetag to whichever team has a spot for him to play every down and do his thing.

LB Frankie Luvu (Panthers) — Would the Jets want a reunion with Luvu, who began his pro career with them as an undrafted FA in 2018? He did a little bit of everything for Carolina the past two years, including starting all 17 games in '23 and notching a career-high 125 tackles, 5.5 sacks after scoring seven sacks in '22, 11 QB hits and two forced fumbles.

DEFENSIVE BACKS

Jordan Whitehead, who came to the Jets as a UFA in 2022, began last season with a bang, three picks in the OT win over Buffalo, and finished with career highs in picks, tackles and PDs. He could become free again, as could takeaway magnet Ashtyn Davis and "we hardly knew ye" Chuck Clark, the FA from Baltimore who suffered a season-ending injury in training camp. But Tony Adams came into his own as the high-energy second-year UDFA partner to Whitehead. Corner looks to be well-populated with Sauce Gardner, D.J. Reed and Michael Carter.

S Xavier McKinney (Giants) — The Jets could corner the market on X-men (along with Xavier Gipson and Xavier Newman) if they were to bring McKinney from his Giants locker room at MetLife Stadium to the Jets' quarters. McKinney had three INTs last year along with career highs in PDs (11) and tackles (116). S Antoine Winfield Jr. was tagged Tuesday, removing the possibility of the Jets signing a four-year Tampa Bay starting safety for the second time in three offsseasons.

CB Kendall Fuller (Commanders) — Unlike safety, the UFA cornerbacks class is thin. Fuller may be the best of the potentially available CBs. He's entering his ninth NFL season, and in his last four, all with Washington, he started 62 games and had 10 INTs. KC's L'Jarius Sneed and Chicago's Jaylon Johnson both received non-exclusive franchise tags.

S Chauncey Gardner-Johnson (Lions) — "Ceedy Duce" has bounced around as a pro, from the Saints to the Eagles in '22 to the Lions last season, where he played only three games before tearing his pectoral muscle to end his season. When he's available, he'll make turnovers for his team (league-lead-tying 6 picks for the Eagles). It may mean nothing, but when Gardner-Johnson was drafted by New Orleans in '19, it was with the 105th overall pick that they acquired in a trade with the Jets.