At 6-foot-2 and 237 pounds, Manning was originally selected in the fifth-round by the Green Bay Packers in the 2012 draft. Manning was claimed off of waivers after final cuts in September 2013. Manning was later released and added to San Diego's practice squad after Week 3.
Manning was active for one game for the Chargers in 2013. With the North Carolina State product no longer with San Diego, the Chargers have six inside linebackers on the 90-man roster -- Donald Butler, Manti Te'o, Kavell Conner, Reggie Walker, Andrew Gachkar and Jonas Mouton.