The Millers players have been training twice a day at their pre-season training base in Portugal and it's another early start tomorrow.
Gaffer Evans told the clubs official website: "The lads fitness levels are improving rapidly now and I must say they have worked as hard as any squad we have worked with. This trip has been outstanding so far given the quality of work we have been able to get into them.
"We will be working them at 7.30am in the morning before they have a wee rest ahead of the match with Oldham Athletic. Every player on the trip apart from Dale Tonge and Michael O'Connor will play a part in the match. Both those lads are working incredibly hard but we are not going to be taking risks with any player who is not 100%."
We'll have updates on the game on MillersMAD throughout Wednesday morning.
The Millers fly home on Thursday to prepare for their first ever game at the New York Stadium on Saturday against Barnsley.