The experienced 29-year-old sustained a rib injury during his side’s 41-17 reverse to Western Province at Newlands at the weekend.
Potgieter has generally been a sound acquisition for the under-performing union having been re-signed in March following a stint overseas and has exhibited a professional attitude amidst the rise of 20-year-old prodigy Handre Pollard, which kept him out for the latter stages of Super Rugby.
He also managed to keep his head as others faltered during the current false start.
Tony Jantjies is now expected to don the No 10 jersey and at least Vodacom Cup pivot Tian Schoeman is back from his own long-standing affliction to provide cover.
Tighthead Morne Mellet is also out for four weeks with a knee problem.
The Bulls play their first home game of the campaign against the Kings on Saturday.