Murray had hoped to make his comeback against Gillingham on Easter Monday and travelled down to Kent with the rest of the squad only to discover his foot had swollen up again.
Johnson said: "There are just three games left and Scotty is not close. It will be very fortunate if we see him before the end of the season.
"It is a shame for Scotty but he is still in the dressing room smiling and he is a great personality to have around the place."
Sporting Life