Boss Ronnie Moore brought in Drewe Broughton and Andy Nicholas to his starting line up and it was Broughton who almost opened the scoring for the Millers but his early header from Dale Tonge's cross was just wide.
Lee Hughes responded for County shortly afterwards but his play acting antics were the main talking points of a first period which also saw Mike Edwards hit the bar with a header from Ben Davies' free kick.
After Fenton's exit for his trip on Davies Rotherham began to defend deeper and goalkeeper Andy Wsrrington twice denied the visitors the opening goal.
The stopper stretched superbly to tip sub Luke Rodgers' drive over the crossbar and then denied the lively Davies from a free kick moments later.
The Pies dominance seemed set to pay off when Ade Akinbiyi rounded Warrington in the closing minutes but saw his side foot effort cleared by Jamie Green as the ball travelled goalwards.
And their day was summed up in stoppage time as Rodgers had the ball in the net but it was ruled out for an offside flag.