The Jets defense got a face-lift Monday.

Jets general manager Darren Mougey and head coach Aaron Glenn focused on defense on the first day teams could negotiate with free agents. They added five new defensive players — four through free agency and one in a trade with one of their rivals, according to sources.

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The Jets committed $117 million in new contracts as they try to upgrade a defense that was 31st in points and 25th in yards allowed in 2025.

Mougey started Monday off by swinging a trade with the Dolphins to acquire veteran safety Minkah Fitzpatrick for a seventh-round pick. As part of the deal, the Jets are giving Fitzpatrick a new three-year, $40 million contract.

That trade came a few hours before the negotiating window opened for free agents. When it did, Mougey and Glenn wasted no time reaching deals with veteran linebacker Demario Davis, defensive tackle David Onyemata, safety Dane Belton and edge rushers Joseph Ossai and Kingsley Enagbare. None of these signings — or the trade — can become official until 4 p.m. Wednesday.

The Jets clearly prioritized defense after a terrible 3-14 season that saw the defense allow a whopping 503 points and force only three fumbles and no interceptions.

The Jets also wanted to land some leadership on defense and Fitzpatrick and Davis both fit the bill. Glenn is taking over defensive play calling in 2026 and needs players who can help him teach the defense. Both Davis and Onyemata were with the Saints when Glenn was an assistant coach there.

Fitzpatrick, a New Jersey native, has played eight years for the Dolphins and Steelers. The 29-year-old started 14 games for Miami last year and had one interception. He has only two interceptions in his past three seasons after having six in 2022. Fitzpatrick is a five-time Pro Bowler, including in 2024, and was first-team All-Pro three times, the last time coming in 2022.

New Jets defensive coordinator Brian Duker was the secondary coach last year in Miami, so he and Fitzpatrick have familiarity.

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Davis returns to the Jets for a third time on a two-year, $22 million deal that includes $15 million guaranteed. The 37-year-old was originally drafted by the Jets in the third round in 2012. After one year with the Browns, he returned to the Jets in 2017 in a trade but then departed again as a free agent. He spent the past eight years with the Saints, going to two Pro Bowls.

Davis had 143 tackles and two forced fumbles last season for New Orleans. Glenn spoke glowingly of Davis before the Jets faced the Saints last season. They were together from 2018-20 in New Orleans.

“He is probably one of the best leaders that I’ve ever been around,” Glenn said in December. “I think he’s 37 years old playing that position, man you hardly ever see that. So, nothing but respect for him. I love the player and I love what he brings to the table. … He’s A1 in my book.”

Davis will help the Jets run defense, which was 29th last season.

The team also beefed up its pass rush, which got very thin after trading away Jermaine Johnson. Ossai agreed to a three-year, $34.5 million deal that includes $22.5 million guaranteed. Ossai, a third-round pick in 2021 by the Bengals, has had five sacks in each of the past two years. He also forced two fumbles in each of those years.

They also agreed to a one-year, $10 million deal with Enagbare. He was taken in the fifth round in 2022 by the Packers, whom he has played for the past four years. He has 11.5 career sacks, with 2.5 last year. He is known as a strong run defender.

Onyemata gives the Jets another defensive tackle, joining Harrison Phillips, Jowon Briggs and nose tackle T’Vondre Sweat in the middle of the defensive line. The 33-year-old is another player that Glenn knows from the Saints. Onyemata was in New Orleans from 2016-22 before playing for the Falcons the past three years. He had 62 tackles and a sack last year.

Belton comes to the Jets from the Giants, where he started 22 games in four years. The Jets gave him a one-year, $4 million contract. He figures to be a third safety and special teams contributor.