The incident occurred in the 23rd minute when Farah attempted to pressure a kick from Canterbury five-eighth Josh Reynolds.
Farah's head appeared to make contact with Reynolds's hip before the 32-year-old's head slammed into the ANZ Stadium turf.
Play was stopped for eight minutes with medical staff from both clubs monitoring his wellbeing before he was stretchered from the field to a rousing round of applause from the 20,936 fans in attendance.
Club officials said Farah was conscious and moving and it is believed he was sent to hospital shortly after half-time.