Richards, who is represented by Doyle Management Group, confirmed his agreement with the Chargers after the conclusion of the NFL Draft late Saturday.
"I'm very blessed and grateful for this opportunity," said Richards who earned AFCA and Associated Press All-America honors for the Bears in 2012. "I cannot wait to get to work."
Richards served as MSU co-captain and started all 11 games at right tackle for Terry Allen's MSU club this season. He carried out a 98-percent assignment grade in 2012, had 56 knockdown blocks and graded out at 85 percent overall. He was named by the Missouri valley Football Conference as an All-MVFC second-team selection and later was named MSU's Offensive Lineman of the Year.
He anchored an MSU offensive line that surrendered just 15 sacks on the season and averaged 327.5 yards per game. During his two-year career in Springfield, Richards started all 22 games and earned MSU Offensive Lineman of the Week distinction for key games against Kansas State (Sept. 1) and North Dakota State (Nov. 3) this season.
Richards is in a group of 20 undrafted free agents who signed with the Chargers on Saturday. The group will be part of rookie camp when it opens in late July in San Diego. The Chargers 2012 draft class includes top pick D.J. Fluker of Alabama as well as Notre Dame standout Manti Te'o.