With Andy Warrington in goal and three other senior players featuring including trialist Jeff Smith, Rotherham grabbed the victory in the second half at Roundwood sports ground.
Gareth Evans gave the visitors the lead before the break firing in from 18 yards before the home side hit back ,but Luke Beedham netted with an unmarked header late in the game to seal the spoils.
Millers: Warrington, Smith, Rose, Lindsay, Foltyn-Brown, Royles, Marshall, Walker, Woods, Denton, Evans.
Subs used: Williams, Hart, Beedham.