He did all the necessary workouts this offseason. His progress from a spinal cord contusion sustained against Washington seemed to be headed in the right direction.
But McClain has yet to be cleared for contact and is on the physically unable to perform list.
On Thursday, coach John Harbaugh said that while the organization anticipated McClain's return for training camp, the doctors are exercising extreme caution because he's not 100 percent, even if he feels like he is.
"When you look at MRI and you see what's on there, there's no denying the fact it's not safe for him at this time," Harbaugh said.
It's unclear how long McClain will stay out for, or what the underlying problem is that's causing his MRI to come back the way it is. It's also unknown if he'll be ready for the season-opener, or if he'll remain on the PUP list for the first six games of the regular season.
With McClain out, it's giving rookie linebacker Arthur Brown an opportunity to gain some valuable reps. In Thursday's practice, he worked with both the first and second units. Josh Bynes and Daryl Smith also saw a lot of time rotating between both units.
The Smith addition could prove to be a major addition if McClain's issue lingers. Smith spent most of the 2012 season injured but played the final two games of Jacksonville's season. Healthy again, he could provide a veteran presence at inside linebacker if McClain is unable to when the season starts.
"That was a big move," Harbaugh said. "[Linebackers coach] Ted Monachino had a lot to do with that. Ted coached him down in Jacksonville, so he knew him so well, and he’s been better than advertised as a leader and as a football leader one day in."
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