
The Potchefstroom-born front-rower, who joined the Johannesburg outfit in 2010, had undergone surgery on his wrist which will potentially see him on the sidelines for up to six months.
25-year-old Dreyer joins fellow front-rowers, Malcolm Marx and Julian Redelinghuys, on the injury list after he fractured his wrist against the Kings last week.
The current front-row conundrum could force regular loosehead prop Jacques van Rooyen to migrate to the opposite side of the scrum as a replacement for Dreyer.