The Ravens announced they signed center Hroniss Grasu on Monday. The team waived defensive back Robertson Daniel in a corresponding move.
The move leaves the Ravens with three reserve offensive linemen -- Orlando Brown Jr., Bradley Bozeman and Grasu -- and four healthy cornerbacks unless Anthony Averett is ready to return from a hamstring injury.
The Ravens promoted Daniel from the practice squad last week, and he played 10 special teams snaps against the Broncos.
The Bears drafted Grasu in the third round in 2015. He was one of 10 offensive linemen who worked out for the Ravens a week ago, and he also has had a tryout with the Vikings.
He started 12 games in his three seasons in Chicago.