Gilly has dislocated the shoulder that he injured at the back end of last season meaning that he will be out for a lengthy spell, maybe the season.
With the absence of Gilchrist it leaves Mick Harfords squad wafer thin, a subject he spoke about today.
"The squad as thin as it is, we can't afford to lose players like Scott Minto and Phil Gilchrist, we're getting wafer thin now."
"It's inevitable that you will get injuries and suspensions, the injuries have come at a bad time but at the moment we have just got enough back-up to keep us covered but if we pick any more injuries up we might be in a bit of trouble."
Trialists Chris Thackery, Paul Hall and Grant Leadbitter have all played in tonights reserve game against Oldham which the Millers lost 1-0