The Saints placed Gillikin (back) on injured reserve Wednesday, per the league's official transactions report.
Gillikin made New Orleans' initial active roster, so he'll be eligible for activation from IR after a minimum of three weeks. In the meantime, Thomas Morstead will handle punting duties for the Saints.
GIllikin is on the Saints' final 53-man roster, Amie Just of Nola.com reports.
In a surprising move, the Saints opted to keep two punters on the roster, with mainstay Thomas Morstead being the other. Gillikin came to New Orleans as an undrafted free agent from Penn State.