Jennings, a seventh-round pick of the Jaguars in 2009, started six games last season in place of an injured Maurice Jones-Drew. Last season, Jennings rebounded from a season-ending knee injury suffered in a 2011 preseason loss at Buffalo. Jennings rushed for 283 yards and two touchdowns in 10 games in 2012, but didn't appear in a game for the remainder of the season after suffering a concussion in Week 13 against the Bills.
Jennings (6-1, 230) is a power runner that could fill the void left by Mike Goodson when he signed with the Jets at the start of free agency. In three NFL seasons, Jennings has rushed for 944 yards and seven touchdowns. Jennings averaged at least 5.0 yards per carry in each of his first two seasons. The Raiders plan on returning to a power blocking scheme in 2013 after struggling with former offensive coordinator Greg Knapp's zone-blocking attack last season.
Smith, a third-round pick of the 49ers in 2008, did not play in 2012 after he was released by the Panthers in August during final cuts. In four seasons in San Francisco, Smith recorded 64 tackles and two interceptions. The Raiders were in need of safety help after the release of one-time All-Pro free safety Michael Huff last month.
It has been a tumultuous offseason for Oakland. In addition to losing Huff and Goodson, the Raiders have also parted ways with quarterback Carson Palmer, wide receiver Darrius Heyward-Bey, defensive tackle Tommy Kelly, linebacker Rolando McClain and tight end Brandon Myers.
The Raiders own the No. 3 overall pick in the first round of the draft, but only have three selections during the first four rounds.
Keep your eye on everything NFL by following Matt Rybaltowski on Twitter @mattrybaltowski.