The Millers only made 3 changes from the weekend win over Lincoln and striker Andre Green made his first start for the Millers after spending 14 months on the sidelines with an Achilles injury.
Jonson Clarke-Harris, Zak Jules put the Millers 2-0 up before Tranmere pulled one back, with Hakeem Odoffin netting for the Millers to put the game out of Tranmeres reach.