"I don't think we've actually played or trained on grass since the Leicester game" said the boss.
"Liam Davis had a hernia operation last week so he is obviously unavailable and Luke Guttridge suffered a small set back with his knee and hamstring injury in training on the Astroturf this week.
"Apart from those two though we have got a fully fit squad and we are all just chomping at the bit to play some football."
At Boundary Park tomorrow the Town defence will have to contend with 15 goal striker Lee Hughes and veteran Dean Windass.
"The legs might go but the brain doesn't change." said Gray. "I've seen Oldham play three times now and I think Windass has been involved in all the goals I've seen them score.
"He drops in, he can play the ball around the corner first time and he can play a pass. You don't need legs to do what he does, it's just a question of reading situations.