Detroit Lions injury update: John Cominsky, DJ Reader, Netane Muti

The Detroit Lions made it through their first padded training camp practice on Monday with no injuries. Tuesday's session was a different story. Defensive lineman John Cominsky suffered a right knee injury after being rolled up on, and guard Netane Muti left practice due to a left shoulder issue.

Cominsky had to be carted off the practice field after trying to walk off under his own power. While that increases the concern level that it's a major injury, a full evaluation is still to come and the cart is an easy precaution in a situation like that.

Cominsky has been getting reps with the third-team defense so far in training camp, which is a sign he's somewhere on the roster bubble after taking a pay cut this offseason.

Muti has sort of surfaced as an early sneaky candidate to make the Lions' roster. He has been working regularly with the second-team offense.

Detroit Lions injury updates

Before Tuesday's practice, Lions head coach Dan Campbell had a update on rookie guard Christian Mahogany, who continues to miss practice due to an illness and is on the NFI (Non-Football Injury) list.

"Yeah, really, I can't, I don't want -- here's what you do know," Campbell said. "Any time a rookie's missed, here we go, we're going on practice six and he's still not here, yes, you get concerned with the development of the player because they need everything. You miss one day as a rookie and that's tough to recover from because you don't have two-a-days anymore."

"I don't want to say we're concerned. And it's a real thing, you know, this illness. It really is a day-by-day. We have virtually checked him in, so he's virtually in meetings and things of that nature. But, when we know he's ready to get here and be a part of what we're doing, believe us, we'll get him here as fast as possible. But as of right now, we have to assume we don't have him."

Running back Zonovan Knight and undrafted rookie wide receiver Jalon Calhoun were absent from Tuesday's practice for undisclosed reasons. Defensive back Brian Branch was in pads, but limited, as was safety C.J. Moore.

Defensive tackle DJ Reader remains on the PUP list as he works his way back from a torn right quad tendon last season. After he casted some doubt on his status for the season opener recently, he talked with ESPN's Eric Woodyard on Tuesday.

Cominsky's injury is the biggest injury headline for the Lions on Tuesday, and of camp so far. An update, for better or possibly worse, seems likely to come on Wednesday.

Update, 4:55 p.m. ET: According to multiple reports, Cominsky suffered a torn MCL and is expected to miss the entire regular season.