Detroit will need answers without Tulloch

ALLEN PARK, Mich. -- Stephen Tulloch was hopeful Sunday afternoon, even if the early evidence showed otherwise.

Tulloch injured his left knee celebrating a sack of Aaron Rodgers, a player he has faced multiple times in his career and has a tremendous amount of respect for. In doing so, he'll watch the rest of the Detroit Lions' season from the sidelines after injuring the ACL in his left knee.

It'll be the first time Tulloch will miss games in his NFL career and for him, for the Lions, the injury couldn't have come at a worse time. Detroit's defense was starting to show signs of being a really strong unit this season with Tulloch in the middle backing up the defensive line.

The way new Lions defensive coordinator Teryl Austin was scheming, too, fit Tulloch's game so well. In three games, Tulloch already had two sacks -- inching closer to his career-high of 3.5 set last season. He was able to blitz more than he had in the past and was provided with open rush lanes because of Detroit's defensive front.

He was a major asset next to emerging star DeAndre Levy at linebacker, a consistent player who never got hurt and had five straight seasons of 110-plus tackles in the middle of the Tennessee and Detroit defenses.

Now, with one celebration, his 131-games played streak is over. His 100-plus tackles streak is over. And the Lions have a massive hole to fill in the middle of their defense, a defense that has already had to deal with season-ending injuries to two cornerbacks.

Tulloch can't even know how his body will respond to this because he hasn't been injured on the professional level before. He doesn't know what it is like to watch from the sidelines -- something he was frustrated with even after Detroit's win Sunday.

This is going to be an adjustment for him.

It'll be a shift for the Lions, too.

Detroit coach Jim Caldwell didn't indicate how the team will replace Tulloch in the middle, but the immediate option would seem to be sliding Levy over to the middle to handle setting the defense, something he did after Tulloch's injury Sunday.

Levy is exemplary in his preparation each week, so making that shift shouldn't be a huge deal for him, but it will take some getting used to. Theoretically, though, it might take some coverage responsibilities away from Levy if they made the move. That could be problematic for the Lions because Levy is one of the best coverage linebackers in the NFL -- proven again Sunday when he broke up a fourth-down pass in the end zone while covering Green Bay receiver Jordy Nelson.

Another option would be Tahir Whitehead, who backed up Tulloch intermittently during the preseason and spring workouts. Moving him to the middle would allow Levy to stay where he might fit the defense the best and it still keeps the Lions' top two available linebackers on the field.

Ashlee Palmer would then likely slide into Whitehead's spot in Detroit's base 4-3 defense, at least until Kyle Van Noy returns from abdominal surgery.

The third option for the Lions is to try and sign a veteran linebacker off the street, although there aren't a ton of options available. Pat Angerer is a middle linebacker who has experience with Caldwell from their time in Indianapolis together and he was released from Atlanta during the preseason. Former Saints linebacker Jonathan Vilma is also a free agent.

Detroit recently signed linebacker Jerrell Harris to its practice squad and released Brandon Hepburn, who landed on Philadelphia's practice squad.