Mailbag: How will Detroit Lions do with Stephen Tulloch back?

Training camps get under way all across the NFL this week. Although the Detroit Lions still have a week to go before they start their on-field road to the 2015 regular season, a bunch of questions are starting to come in about what will happen this season and what it will take to make a second straight playoff appearance.

So with that, we'll start to try and answer them. To ask a question for the Mailbag, use the hashtag #LionsMailbag on Twitter, email me at michael.rothstein@espn.com or drop me a note at my Facebook page.

Now, on to your questions.

@mikerothstein: In theory, it should be one of the strongest groups on the Lions. It has some of the most depth, especially since both Tahir Whitehead and Josh Bynes performed well in Tulloch's absence. If Kyle Van Noy comes along as Detroit hopes, that gives the franchise five linebackers it can count on to be not just special-teams players who are emergency fill-ins due to injury. Specifically with Tulloch, he's never been seriously hurt as a professional before and based on what he has said and his Instagram posts, he's been working out maniacally to get back. He's one of the guys I'll be watching the most the first week in pads to see if that work has translated to a return to form.

@mikerothstein: As mentioned before, I'd like to see Tulloch in pads before deeming him ready to go. He's looked good running, though, so that's a good first step. The players to really watch here are running back Joique Bell, right tackle LaAdrian Waddle and, to an extent, defensive tackle Jason Jones and linebacker DeAndre Levy. Levy didn't do many team drills in the spring but that seemed to be a planned strategy. As long as he's out there in full in August, the Lions are fine there. Jones missed minicamp to deal with an injury, but he's expected back for the start of camp. Waddle's timeline to return from his knee injuries is still unknown, so that's a concern. Bell is also a concern because he didn't practice all spring. Though he's expected back at some point soon, until he's on the field I would be cautious there.

@mikerothstein: That's one of the biggest questions of the preseason. I'm pretty high on the linebackers and think they'll be a strong unit overall. The back seven should actually be quite good, especially if the Lions get the nickel slot sorted for passing downs. The big issue is at defensive tackle, where there are still a lot of unknowns. What will Haloti Ngata look like on a new team? Does he still have a lot left in the tank? Who plays next to him? What does the rotation look like and can any of them really rush the passer well? If Detroit answers those questions well, then the Lions could be in good shape to still have a Top 10 defense and possibly a playoff berth. If not, teams can plan to run against Detroit's front four, forcing the Lions to adjust coverages and potentially put more pressure on the secondary. It'll be something to pay attention to during the preseason and then specifically in Week 2 -- when Detroit faces Adrian Peterson.

@mikerothstein: Barring injuries to others, it'll come down to special teams for Zenner. If he outperforms George Winn and some players at other positions, then he could be on the 53-man roster. If he doesn't, then he won't be and could end up on Detroit's practice squad. Right now I'd put it at a little bit less than 50-50.