Waller (undisclosed) was sidelined during OTAs, ESPN's Jamison Hensley reports.
Waller joins a long list of Ravens tight ends that are dealing with injuries as Ben Watson (Achilles), Crockett Gillmore (shoulder) and Maxx Williams (knee) weren't available for OTAs either. However, it isn't clear what kind of injury he's dealing with or if he'll be back in time for training camp.