The Ravens reinforced their safety room Tuesday following Marcus Williams' pectoral injury in Sunday's season opener.
Veteran defensive back Daryl Worley was signed to the 53-man roster, while safety Duron Harmon was signed to the practice squad.
Worley saw action in Sunday's 25-9 victory over the Houston Texans, playing three defensive snaps and 20 snaps on special teams after being elevated from the practice squad.
Williams suffered a pectoral injury Sunday and "will be out for a while" according to Head Coach John Harbaugh. As of Monday, Williams and doctors were still determining whether he would undergo surgery. Harbaugh said a decision would come soon.
The 28-year-old Worley can play both safety and cornerback and appeared in eight games for Baltimore last year, making one start.
Harmon started 16 games for the Raiders last season and had 86 tackles, two interceptions and two forced fumbles. The 32-year-old Harmon is an experienced veteran who spent his first seven seasons with the Patriots, winning three Super Bowls in New England. For his career, Harmon has 401 tackles and 23 career interceptions, with at least two picks in each of the last six seasons.
Worley takes the roster spot of running back J.K. Dobbins, who was officially placed on injured reserve following Sunday's season-ending Achilles injury, while cornerback Tae Hayes was released from the practice squad.