That's the result of getting poked, punched, and kneed in the face by a UFC heavyweight contender.
Taking on Travis Browne at UFC Fight Night 81 in Boston, Mitrione suffered a TKO loss, but much of the focus post-fight rested on Mitrione's alien-like hematoma. The UFC's official Twitter account captured the destruction:
After eating a stiff right hand in Round 3, Mitrione's eye swelled to epic proportions, and the end was near.
Browne drug the fight to the mat, advanced to full mount, and sealed the deal with a series of punches and elbows from top position.