Walker didn't participate in Tuesday's practice while tending to an undisclosed injury, Jeff Zrebiec of The Athletic reports.
Per Giana Han of TheBaltimoreBanner.com, Walker was in uniform for the practice session, but he was working out to the side and mostly limited to agility work. The Ravens will post their first Week 1 injury report Wednesday, when the nature of Walker's health concern -- as well as the extent of his practice participation -- will be revealed.