O'Brien was confirmed as Meath manager on 10 November 2008 after a meeting with the county board to succeed Colm Coyle.
[1] His team had a reasonably successful 2009 season, where they were defeated by Dublin in the Leinster quarter finals, but went through the qualifier system to reach the All-Ireland semi finals, where they were defeated by Kerry.
[2] In this match, Meath forward Joe Sheridan was awarded a goal in the final minutes which on replay evidence should not have stood, to give Meath a 2-point win.
Meath went on to be beaten by Kildare in the All-Ireland Quarter Finals.
On 6 September 2010 O'Brien was unexpectedly axed as manager after many of the county's clubs voted him out.