Armstrong was not selected in the 2013 NFL Draft but was signed as an undrafted free agent by the St. Louis Rams. He was claimed off waivers by the Oakland Raiders in October of 2014 and waived on Tuesday.
He has 44 tackles, one sack, and one forced fumble during his career. Armstrong was Second-team All-ACC in 2010.
Earlier this month, Armstrong got into some trouble by taunting a police dog. While in Pittsburgh to play the Steelers, he lifted his shirt, pounded his chest and barked at the dog before telling the dog's handler to let it off the leash. In Pennsylvania, taunting a police dog is a third-degree felony. Armstrong was not charged.
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