The Giants realized they need some returning veterans on their defense.

After letting safety Landon Collins walk away in unrestricted free agency and trading outside linebacker Olivier Vernon — on the heels of the in-season trades of cornerback Eli Apple and nose tackle Damon Harrison — the Giants owe a $6 million roster bonus Friday to inside linebacker Alec Ogletree, according to the terms of his contract.

A roster bonus is just like it sounds like: A bonus just for being on the 90-man roster Friday.

Ogletree’s salary cap hit in 2019 will be $11.75 million, which trails only cornerback Janoris Jenkins among those defensive players returning to a new-look defense. The Giants could have saved the $6 million by dumping Ogletree before today, but they would have incurred $5.75 million in dead money on the cap.

Only Luke Kuechly (Panthers) and Bobby Wagner (Seahawks) have higher salary cap hits than Ogletree among NFL inside linebackers in 2019. Ogletree originally signed this contract with the Rams.

Acquired last March via trade along with a seventh-round draft pick in 2019 in exchange for two draft picks in 2018, Ogletree restructured his contract upon arrival. He took a $7 million roster bonus in 2018 and converted it into a signing bonus spread into four equal annual salary cap charges of $1.75 million.

It is possible the Giants could ask Ogletree to make the same conversion but Gettleman referred to that strategy as “kicking the can down the road.”

Ogletree, who brought a needed sense of accountability to the locker room during the first year of the coach Pat Shurmur/general manager Dave Gettleman regime, and Collins were the Giants defensive co-captains.

Ogletree finished with 93 tackles, one sack and a team-high five interceptions, including two returned for touchdowns in 13 games anchoring the 3-4 defensive front.

But Ogletree also allowed 51 catches for 532 yards and three touchdowns in coverage, according to Pro Football Focus. He was downgraded to the No. 81 linebacker in the NFL by the analytics site because of his struggles covering tight ends and running backs.

The Giants signed safety Antoine Bethea and edge-rusher Markus Golden as free agents from the Cardinals and acquired safety Jabrill Peppers in the Odell Beckham trade with the Browns.

Inside linebacker, where B.J. Goodson and Tae Davis are the only other players returning from the 53-man roster, is a need, but is not as big as another edge-rusher and a starting cornerback as long as Ogletree is on board.

Ogletree is under contract through 2021 but only has $3.5 million in guaranteed money due in 2020.

The Giants have another major roster bonus decision up next: Quarterback Eli Manning is due $5 million Sunday to up his salary cap hit to $23.2 million. All indications are the Giants intend to bring back Manning but there has been no definitive answer when asked if they will try to restructure his contract.

Ryan Dunleavy may be reached at rdunleavy@njadvancemedia.com. Follow him on Twitter @rydunleavy. Find our Giants coverage on Facebook.