The San Diego Chargers were busy adding depth to their defense on Sunday.

The Chargers announced that they traded a 2015 conditional seventh-round pick to the Cowboys for defensive tackle Sean Lissemore. They also claimed defensive lineman Drake Nevis (Colts) and linebacker Terrell Manning (Packers) from waivers.

San Diego also signed linebacker Reggie Walker, who was brought on to participate on special teams.

To make room for these roster spots, San Diego released defensive end Brandon Moore and linebacker D.J. Smith, and moved defensive end Damik Scafe to injured reserve.

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Aaron Wilson covers the Ravens for The Baltimore Sun.