The Ravens have signed veteran free agent linebacker Daryl Smith to a one-year contract, a transaction intended to bolster depth at inside linebacker. Although terms weren't immediately available, sources told The Baltimore Sun this wasn't an expensive investment. The Ravens cut oft-injured outside linebacker Michael McAdoo to create a roster spot for Smith. Smith, 31, is the Jacksonville Jaguars' all-time leading tackler and is entering his 10th NFL season. By acquiring Smith, the Ravens have significantly upgraded the experience level at inside linebacker. The 6-foot-2, 248-pound former second-round draft pick from Georgia Tech has recorded 678 career tackles, 21.5 sacks, six interceptions and nine forced fumbles. Smith started two games and recorded six tackles last season due to a groin injury that forced him to miss most of the season on the injured reserve-designated to return list. However, he had started every game the previous three seasons. In 2011, Smith had 107 tackles, one interception and two forced fumbles with a career-high eight pass deflections. Smith visited the St. Louis Rams in April, but left town without a deal. The Ravens could use some experienced depth at inside linebacker after Ray Lewis retired this offseason and Dannell Ellerbe signed a $35 million contract with the Miami Dolphins. Plus, starter Jameel McClain still isn't fully cleared from a spinal cord contusion, Rolando McClain retired while dealing with multiple legal problems and second-round pick Arthur Brown is sidelined until training camp after undergoing sports hernia surgery.