[6] A former Heavyweight contender, he has several wins over notable MMA fighters, including Kimbo Slice, Derrick Lewis, Roy Nelson, Phil De Fries, and Fedor Emelianenko.
Mitrione was born in Bloomington, Illinois and raised in Springfield, where he attended Sacred Heart-Griffin High School for first four years, where he competed in football, swimming and diving, and track and field.
He attended Purdue University on a football scholarship and started 35 consecutive games for the Boilermakers at defensive tackle, but broke his right foot during winter conditioning practice in his senior year.
Mitrione then relocated with his family to Indianapolis, Indiana, where he began training with fighters Chris Lytle and Jake O'Brien.
After being picked second to last by Evans, Mitrione fought and defeated Scott Junk via majority decision (19–19, 20–18, and 20–18), moving him on to the quarter-finals.
Mitrione did fight and was eliminated by teammate James McSweeney in the quarterfinals, losing via guillotine choke.
Mitrione made his professional MMA debut on December 5, 2009, at The Ultimate Fighter: Heavyweights Finale defeating Marcus Jones via KO early in the second round.
[14] Mitrione then faced another fellow Ultimate Fighter alumnus Kimbo Slice at UFC 113 in Montreal.
[30] On April 8, 2013, it was announced that Mitrione had his contract suspended by the UFC after making comments about male-to-female transgender fighter Fallon Fox during an interview on The MMA Hour.
[50] After being dropped by an overhand right by Seumanutafa, Mitrione recovered on the ground and eventually won the fight via knockout in the first round.
[53] Mitrione was scheduled to take on Fedor Emelianenko at Bellator 172 on February 18, 2017, in San Jose, California.
Mitrione went on to win the fight by way of majority decision, avenging his prior loss to Nelson in the process.
[61] The bout ended in a No Contest fifteen seconds into the first round after Mitrione landed an accidental groin strike leaving Kharitonov unable to continue.
[63] Mitrione's mouthpiece repeatedly fell out of his mouth, and he eventually lost the fight via knockout in the second round.
[64] Mitrione stepped in to replace Josh Barnett, who failed his medical tests, to face Ronny Markes at Bellator 241 on March 13, 2020.
[72] Mitrione protested the stoppage due to an accidental clash of heads that occurred before Fortune secured a takedown.
[74] According to Mitrione, he was scheduled to face Kubrat Pulev on November 27, 2021, in a boxing vs MMA card promoted by Triller that featured other UFC veterans.
[76] In November 2021, Mitrione all but stated he was retired from MMA, leaving his career open to mixed rules bouts but probably nothing more.
He is friends with Drew Brees, as the two were teammates at Purdue University from 1997 to 2001 and members of Joe Tiller's first recruiting class.
[80] He is also close friends with former NFL tight end Jeremy Shockey, who was his teammate while playing for the New York Giants.
[83][84] Mitrione has participated in an anti-bullying program with UFC fighters Sean Pierson, Mark Hominick, and Sam Stout in Toronto, Canada.