However, a slight reaction has seen him missing parts of training so as not to aggrevate it.
Manager Brian Little said: "Gary was feeling his back again earlier this week and he didn't take a full part in training but that was more a precautionary measure than anything else.
"A couple of days' rest will do him the world of good and at this stage I don't think there's a problem regarding Friday."
Meanwhile, Little praised the 22-year-old forward for adding another goal to his tally for the season.
"The most important thing to us is that one of our strikers is still very much on goalscoring form because up there we are not functioning as well as we should be.
"We need to keep the ball up in their half of the field more than we are doing at the moment and Gary is at least scoring goals for us and that's giving us a chance to win games."
Elsewhere, Rodney Rowe is returning to fitness after suffering from concussion at Halifax, but isn't expected to be risked against Macclesfield on Friday.
David Beresford is hoping to return to the side after resting a hamstring problem. However, with important games against Rochdale, Mansfield and Scunthorpe coming up he isn't going to be rushed back unless he's fully fit.