McClain was placed on season-ending injured reserve with a spinal contusion and the team elevated linebacker Adrian Hamilton from its practice to the 53-man roster.
So Ray Lewis won't be activated from injured reserve for Sunday's game against the Giants. In fact, the NFL Network is reporting that Lewis won't likely return from his torn triceps before the end of the regular season.
As for Hamilton, he's a 6-foot-3, 251-lb. rookie who was released by the Cowboys after training camp and was signed to Baltimore's practice squad on Sept. 3.
In two seasons at Prairie View A&M, Hamilton recorded 108 tackles, 26 sacks and 34.5 tackles for loss. As a senior in 2011, he broke Colts lineman Robert Mathis' Southwestern Atlantic Conference single-season record with a FCS-leading 20.5 sacks.
McClain suffered his injury Dec. 9 at Washington. His season ends with 79 tackles (57 solo), the second-highest total on the team, in 13 games played.