He played college football at Georgia and was selected by the Arizona Cardinals in the sixth round of the 2003 NFL draft.
As a senior at the University of Georgia (UGA), he earned All-Southeastern Conference second-team honors and started every game at middle linebacker.
He tied for the team lead with a career-high 114 tackles and recorded 2.5 sacks, 15 stops for losses, 13 quarterback pressures, 1 forced fumble and deflected 2 passes.
The move reunited him with Falcons head coach Mike Smith, who was defensive coordinator for the Jaguars during Gilbert's time in Jacksonville.
In 2015, Gilbert joined the University of North Carolina at Chapel Hill as a defensive quality control specialist & assistant linebackers coach.