It’s no secret the Detroit Lions are in need of serious help at linebacker and they’re going after it.

According to a league source, the club is “aggressively pursuing” Stephen Tulloch, another player that coach Jim Schwartz knows well from his days with the Tennessee Titans. Tulloch made 160 tackles last season for the Titans and has not missed a game in his NFL career.

The source says the Lions have offered a signing bonus that reaches eight figures -- $10 million – and they’re waiting to see how the situation will unfold. Schwartz put a full-court press on another former Titan a year ago when he showed up on the door step of defensive end Kyle Vanden Bosch at the outset of free agency. Landing Tulloch would go a long way toward improving a defense that already has a stout line.

If Tulloch enters the mix, he’ll likely play linebacker with DeAndre Levy a candidate to slide over to the weak side. Stay tuned.

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Brad Biggs covers the Bears for the Chicago Tribune