Wide receivers Mark Clayton and Demetrius Williams tweaked their left and right hamstrings, respectively, and Clayton was carted off the field with rookie tight end Davon Drew (right foot) midway through yesterday's morning session. Coach John Harbaugh said Clayton's injury did not seem serious, but said the team is being cautious.
Outside linebacker Antwan Barnes suffered a mild concussion during a full-team drill and lay prone on the turf for about 90 seconds before walking off on his own power. Defensive tackle Lamar Divens was absent for undisclosed reasons.
Fellow wideout Kelley Washington (flu) was activated off the physically-unable-to-perform list.
With 33-year-old center Matt Birk getting a day off as a member of "the 30-plus club," Chris Chester and David Hale rotated at center and right guard with the first offense. Jameel McClain filled in for linebacker Ray Lewis, Haruki Nakamura replaced free safety Ed Reed, and Justin Bannan and Brandon McKinney subbed for defensive linemen Trevor Pryce and Kelly Gregg.