Gary Sawyer will miss a further fortnight with a hamstring problem, with fellow defender Aaron Downes on the sidelines for at least a month with knee cartilage damage.
Goalkeeper Michael Poke is set to feature for the Pirates for the last time with his loan from Brighton due to expire.
McGhee is exploring the option of extending the 26-year-old's stay at the Memorial Stadium but has not closed the door on a swift return to action for former number one keeper Scott Bevan.
He told Gas Player: "If Pokey goes we can look for someone else or Scott can step up. He's got to show me that he's the man, and if he wants the opportunity he can have it."
Defender Adam Virgo (knee) and midfielder Wayne Brown (ankle) remain long-term absentees.