
Jake O'Brien
- Date of Birth: 1984-09-25
- Place of Birth: Indianapolis, Indiana, USA
Biography
Jacob Allen O'Brien is a retired American professional mixed martial artist who most recently competed in the Heavyweight division. A professional competitor from 2005 until 2012, he fought for the UF... Jacob Allen O'Brien is a retired American professional mixed martial artist who most recently competed in the Heavyweight division. A professional competitor from 2005 until 2012, he fought for the UFC, WEC, and DREAM.

UFC 65: Bad Intentions
• 2006 November

UFC 82: Pride of a Champion
• 2008 March

UFC 94: St-Pierre vs. Penn 2
• 2009 January

UFC 100: Lesnar vs. Mir 2
• 2009 July

DREAM 15
• 2010 July

UFC Fight Night 14: Silva vs. Irvin
• 2008 July

UFC Fight Night 6: Sanchez vs. Parisyan
• 2006 August

WEC 19: Undisputed
• 2006 March

UFC Fight Night 8: Evans vs. Salmon
• 2007 January