Jake O'Brien (born September 25, 1984) is an American retired professional mixed martial artist who most recently competed in the Heavyweight division.
Born and raised in Indianapolis, Indiana, O'Brien attended Franklin Central High School where he competed in wrestling, football, and track and field.
O'Brien continued wrestling at Purdue University, and after redshirting his freshman year, posted a record of 14-18 in his sophomore season as the starting Heavyweight.
In his next appearance, O'Brien faced former UFC Heavyweight Champion Andrei Arlovski and was handed his first professional loss via TKO in the second round.
O'Brien failed to make weight, weighing in at 212 lbs therefore was given a 10% purse deduction as well as a yellow card at the start of the fight.