Millers manager Steve Evans has described his side's injury crisis as "emergency ward nine" ahead of the Robins' visit.
The hosts, who were thumped 5-0 at Dagenham last week, could have up to nine players missing, although Evans is hoping to have defender Craig Morgan available.
Morgan limped out of that horror show in east London with an ankle injury, but he returned to training on Thursday and could be in contention.
Midfielder David Noble is also battling with an ankle problem but is on the mend as well, although he is only likely to make the bench if he passes a fitness test.
But that is where the good news ends for Evans, who still has Kari Arnason, Lionel Ainsworth (both shoulder), Kieran Agard (thigh), Dale Tonge (knee/ankle), Scott Shearer (knee), Jamie Devitt (hamstring) and Mitchell Rose (leg) occupying an over-crowded treatment room.
Cheltenham will be without Lawson D'Ath as they look to cement their place in the automatic promotion slots.
The on-loan midfielder has a knee injury and the club plan to speak to Reading to see when he will be fit and whether he'll be able to stay at Whaddon Road.
Defender Harry Hooman returned from his loan spell at Bath with a slight groin problem which rules him out but manager Mark Yates has no other injury worries.
It means the Robins could be unchanged from the team that beat Burton 1-0 last week.
Yates' side have lost just one game in 11 and currently sit in third place in the league, seven points ahead of Rotherham.