2012 Outdoor Earned All-Mountain West Conference honors for his third-place effort in the 800-meter run at the conference championships ... picked up second-place finishing the 800 at the Bobby Lane Invitational, North Texas Invitational and Spec Towns Invite ... also competed in the 4x400-meter relay team, including getting to run at the Penn Relays.
2012 Indoor Took fifth place in the 800-meter run at the MWC Championships ... member of two top-five 4x400-meter relay teams.
2011 In Outdoor, competed in the 800M, 1500M, 4x400 Relay and Distance Medley... Finished second in the 800M and second in the 4x400 Relay at the MWC Championships... Placed second in the 800M at the Tom Jones Memorial Invitational with a personal record time of 1:48.56, good for eighth best in TCU history... Finished second in the 800M and third in the 4x400 Relay at the Michael Johnson Classic... Placed third in the Distance Medley at the Texas Relays... Gained recognition as a member of the Academic All-Mountain West team...Additionally earned USTFCCCA All-Academic and MWC Scholar-Athlete Honors... In Indoor, competed in the 800M, 4x400 Relay and Distance Medley Relay... Finished third in the 800M and sixth in the Distance Medley Relay in the MWC Championships... Received All MWC honors for the 800M... Topped a third place finish in both the 800M and the 4x400 Relay at the Texas A&M Reveille... Placed seventh in the 800M at both the Razorback Invitational and the Tyson Invitational.
2010 Finished the indoor season seventh in the 800 meters at the Mountain West Conference Indoor Championships ... O'Brien made his first postseason appearance at the NCAA West Preliminary Round in Austin after clocking a time of 1:50.39 seconds in the 800 to place fifth overall in a highly competitive field in Albuquerque at the conference championships ... Just missed advancing to the 2010 NCAA Outdoor Championships in Eugene, placing 18th overall in the 800 meters at the NCAA first round with a personal-best time of 1:50.02 ... Advanced at the West Preliminary Round, clocking a preliminary time of 1:50.08 seconds to place sixth ... Collected three runner-up performances during the outdoor season in the 800 at the TCU Invitational, Bobby Lane Invitational and Horned Frog Invitational.
2009 Finished third overall at the Texas Tech Invite in the 800 meters ... Was also part of the distance medley relay that earned sixth overall at the MWC Indoor Championships ... Clocked a personal-best time of 1:51.93 seconds in the 800 meters at the TCU Invitational to place third overall ... Collected runner-up honors in the event at the Horned Frog Invitational ... Finished seventh in the event at the conference outdoor championships ... Helped the men's 4x800 win the LSU Relays with a new complex record.
2008 Cross Country Did not compete during the 2008 season.
Coram Deo Academy O'Brien claimed first-place honors at the TAPPS 4A State meet his senior season after earning runner-up honors the previous year ... A team-captain in track and field, O'Brien also excelled on the gridiron, claiming second-team all-district honors as a senior.