Rotherham's on-loan Arsenal midfielder Mark Randall will go for an X-ray on the shoulder he injured on his debut.
The 21-year-old, who joined from the Gunners last week, lasted only 21 minutes of his debut against Southend on Saturday before sustaining the injury.
And manager Ronnie Moore does not yet know the extent of the problem.
"We don't know how he is yet. He was brave going for a header," he said.
"He's struggling with his shoulder, it's come up straight away and all the tissue is swollen and he'll have to have an X-ray and take it from there."