This is apparently the portion of free agency where the New York Giants are concentrating on their depth, especially on the defensive line.

They re-signed defensive lineman Kerry Wynn on Monday to a one-year deal, according to a source. He returns as a versatile piece who can play inside and out in new coordinator James Bettcher’s defensive scheme.

Wynn, 27, has started 10 career games in four seasons with the Giants. He has 101 tackles and three career sacks, and was known primarily as a run-stuffer from the defensive end position in the Giants' defense under Steve Spagnuolo.

Wynn should be able to help a Giants defense that struggled badly last season (31st in NFL), either as a hand-in-the-dirt lineman or potentially as an occasional set-the-edge outside linebacker. The Giants are believed to be switching to an attacking 3-4 defense under Bettcher, and appear intent on making sure they have depth in the front seven.

Former Arizona Cardinals defensive end Josh Mauro also was visiting Monday. He has familiarity with Bettcher’s scheme from their time together in Arizona.

They also signed outside linebacker Kareem Martin from the Cardinals and traded for linebacker Alec Ogletree from the Los Angeles Rams in an attempt to upgrade the defense.

Wynn was originally signed by the Giants as an undrafted free agent out of Richmond in 2014. He had 1.5 sacks and an interception in five games his rookie season.

After starting seven games and recording 53 tackles in 2015, Wynn has been used sporadically the past two years. He was on the field last season for just 24 percent of the defensive snaps after being retained as a restricted free agent, where he made $1.797 million on a one-year deal.

It didn’t appear likely that Wynn would return with the change of scheme and a new regime, but the Giants decided to reinsert him into the mix on a one-year deal. With his size and frame (listed at 6-foot-5, 264 pounds), he could be a fit as a 3-4 defensive end.

Wynn had 19 tackles and one sack in 15 games in 2017.