The Giants took another big hit on defense when lineman Johnathan Hankins was placed on injured reserve Monday. Andrew Weber USA TODAY Sports

Just when the New York Giants have added a reinforcement along the defensive line in Jason Pierre-Paul, they have lost another. Defensive tackle Johnathan Hankins was placed on injured reserve Monday, and he will miss the remainder of the season with a torn pectoral muscle.

Hankins finished as Pro Football Focus' 69th-best NFL player overall in 2014, and he was arguably the Giants' best defender even with a healthy Pierre-Paul on the field. Hankins anchors the middle of the defense, as the nose tackle, and head coach Tom Coughlin talked about what his absence means Monday.

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"Johnathan, unfortunately, did tear his pec and he will have to have surgery," Coughlin said on his Monday conference call. "He'll be placed on IR and hopefully he will rehab as fast as possible. I don't have a calendar date in terms of how long it will take him to get back, but he does have time.

"John has been a guy that's anchored in the middle of that defensive line for a few years. We'll definitely miss his presence. He knocked the ball out yesterday, he's the one that forced the first fumble recovered by Brinkley. He'll be missed, there's no doubt. He's a strong, strong player inside and he can be a factor against the pass as well as the run. We will definitely miss him."

The Giants will look to defensive tackles Markus Kuhn and second year player Jay Bromley to replace him, but they are now awfully thin at defensive tackle. Cullen Jenkins, who has played a lot of defensive end this season, could kick back inside to tackle as well.