The Millers won six more points on the road (46) than they did at the New York Stadium (40) in League One this season.
Preston have failed to score in six of their last eight league trips to Rotherham, though they did win on both occasions in which they found the net (D2 L4).
The team that finished in fourth place in League One has won the play-offs in each of the last three seasons.
The fifth placed side in League One hasn’t won promotion via the play-offs since 2005/06.
Rotherham have recovered 15 points from losing positions at home this season, a joint-league-high alongside Port Vale.
Joe Garner’s 49th minute strike against Rotherham in the first leg ended a run of 407 minutes without a goal.
The Millers have gone 11 league games unbeaten at the New York Stadium, winning seven (D4).
Rotherham have scored 17 goals in the opening 15 minutes of matches this term; a league-high.