AUBURN, Ala. — At every level of Auburn's defense, the unit is dealing with injuries. Nearly two weeks into the Tigers' fall camp, defensive coordinator Ellis Johnson said that's been "my biggest frustration." As a coach, Johnson pointed out that you enter a camp and "pleasant surprises" and "disappointments" emerge in equal measure.

But then injuries crop up and throw a wrench into even the best laid plans.

"The nagging injuries kind of have us two steps forward, one step back," Johnson said following Thursday's practice. "There are some guys who've got the chance and the skill set to get right into the middle of things, but the limitations in practice have just been holding them back in fundamentals and understanding what we're doing in the scheme."

On the defensive line, a pair of newcomers have been limited recently.

"The frustrating thing is we can't get Devaroe (Lawrence) and DaVonte (Lambert) out there for three or four days in a row. They've been really hampered with nagging injuries," Johnson said of the two transfers from Georgia Military College. "Devaroe hurt his knee and DaVonte's back has been irritating him with just spasms. Nothing really serious, but again, for two new players, missing a couple or three days of practice can really set them back."

Then there is senior defensive end LaDarius Owens. He missed all of spring practice to recover from surgery on his left foot. Now he's dealing with another issue.

"Some infection got into one of his surgeries," Johnson said. "Thank goodness it wasn't anything serious, but it's kept him from getting practice reps. That's set him back a little bit."

Another player who missed the entire spring was defensive back Josh Holsey. He's nearly back to 100 percent, but Johnson said the junior has been watched carefully.

"He's not out, they just want us to limit his reps as he comes back full-speed on his knee," the coach said. " ... It's more of a process they want us to follow in how many reps he gets each day and how much contact, just as a precautionary (measure). He's fully recovered. The summer went very well for him, but obviously you don't have contact during the summer in all the football-specific stuff. So the doctors want us to take a certain path with him and limit his 'pitch count,' that expression we use sometimes."

Other players who have missed time or are battling ailments include linebacker JaViere Mitchell (injury not disclosed), corner Jonathon Mincy (shoulder) and freshman safeties Stephen Roberts (hip pointer) and Markell Boston (right foot sprain).

"We have been really pleased with Boston, then he got hurt. And we've been really pleased with Roberts, and then he got hurt," Johnson said. "For young freshmen, that's a hard thing because when they miss two or three practices, and you're in the middle of installing things, and they miss it, it can be really hard for them to catch up. But I've got confidence that Roberts will get back in the swing, he'll get right back in the mix when he gets healthy."