In a mad opening five minutes, Dean Winnard gave Stanley the lead, heading Charlie Barnett's corner into the top corner of the net.
But it was Winnard's mistake at the other end which gifted Rotherham an equaliser just three minutes later. His backpass went beyond goalkeeper Ian Dunbavin and Nardiello was there to pounce for a simple tap-in from three yards.
Stanley midfielder Rommy Boco came close to adding to the score minutes later but his 25-yard effort was cleared off the line by Johnny Mullins, while Padraig Amond was a threat for Stanley but could not convert a number of half-chances.
Nardiello got his second three minutes after the break in scrappy circumstances. His cross from the left to the near post could not be kept out by Dunbavin.
Stanley made all three substitutions during the second half and pressed without testing goalkeeper Andy Warrington, while Michael O'Connor's 20-yard free-kick after 80 minutes forced Dunbavin into a superb save to prevent a bigger scoreline. Courtney Cameron also came close for the Millers with a blistering strike in injury time.
