Detroit Lions vs. Green Bay Packers

Detroit Lions linebacker Stephen Tulloch (55) missed much of last season with an injury. (Mike Mulholland | MLive.com)

INDIANAPOLIS -- The Detroit Lions defense was supposed to take a hit when middle linebacker Stephen Tulloch went out. It didn't.

Tahir Whitehead filled in capably for the veteran. He was ranked the NFL's 14th best inside linebacker according to ProFootballFocus, even though he had never played the position before, and Detroit soared all the way to No. 2 in total defense.

And that gives the Lions options moving forward.

They could continue to roll with Whitehead at middle linebacker, and carve out some cap space by parting with Tulloch. The 30-year-old is slated to count $5.8 million against the cap next season.

Whitehead costs just $713,000.

Or, the Lions could opt to stick with the battle-tested Tulloch in the middle and use Whitehead on the strong side -- where he began last season -- and on special teams.

General manager Martin Mayhew isn't tipping his hand on how the Lions intend to sort out the logjam. He's just happy to have depth and production at the position.

"The thing with Stephen is his grades were exceptional in all (three) games," Mayhew said. "And I think he was still adapting to the scheme at that time. So I don't think he totally had the whole scheme down.

"As a MIKE linebacker, there's a lot on his plate on the front end and the back end. He's got to make a lot of calls. There's a responsibility he has that a guy like, say, Rashean Mathis or Jason Jones, doesn't have because he's the middle linebacker.

"I think he was still sort of adapting to the scheme, and he was playing lights out. He was playing great."

Tulloch had 20 tackles and 2.0 sacks before suffering a torn ACL while celebrating a sack against Green Bay's Aaron Rodgers in Week 3. He was lost for the season.

The Lions finished off that game with DeAndre Levy at the MIKE, then moved Whitehead there the following week.

Whitehead was exclusively a special teams player his first two years in the league, then made a surprising jump into the starting lineup on the strong side to open the 2014 season. He made the transition into the middle seamlessly, and really came through when the Lions needed him.

He finished with 86 tackles, which trailed only Levy on the team, and two interceptions.

"I never really viewed Tahir as a MIKE 'backer. I thought of him more as an outside guy," Mayhew said. "We had discussions about that. (The coaches) felt very comfortable he could adapt to the MIKE linebacker position, and he did. He did a phenomenal job in there playing for us. He has a very bright future.

"He's a prime example of why you're patient with guys, because his first couple years, he was a special teams guy. And that's what he does. He kind of managed himself doing that -- and then he showed the ability to go in and start for us at MIKE linebacker. Obviously he could start outside for us if we needed him to. So I was very happy with his performance."

That performance prompts one of the more interesting non-Ndamukong Suh questions of this offseason.

Should the Lions stick with the veteran Tulloch at middle linebacker? Or are they better off rolling with Whitehead, who doesn't have the same kind of experience or leadership, but comes at a fraction of the price?

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