The Tar Heels standout fell to the Giants at #52, but his rookie season was lost to a torn pectoral muscle.
Austin saw the field for 103 snaps over eight games in 2012, but was among the Giants' final cuts in 2013.
He would catch on with Miami a few weeks later, but the Dolphins cut him after just two games.
From there, the 6-2, 312-pounder played one game for Dallas, but was waived/injured in November with a back injury expected to have kept him out for several weeks.
PFF has Austin down for a cumulative +0.4 grade over 146 career snaps.
Officially, he's been credited with 10 total tackles in his disappointing career.
Unsurprisingly, Jeff Legwold says the signing of Austin won't affect whether Denver takes a defensive tackle later this week.