Frecklington strike downs Boro
Battered in the first half, the Millers gradually fought their way back into the game and struck five minutes from time to win 1-0 and bank a third successive victory under Neil Warnock.
A draw on the night for MK Dons means the gap to safety is now down to just a point.
Boro could easily have gone into the break 4-0 up.
David Nugent, clean through, sprayed the ball into the kop and play-maker Gaston Ramirez clobbered the post with a delicious free-kick and also had Lee Camp scrambling from 20 yards. With Nugent and Albert Adomah both peppering the home goal, the Millers were relieved to get back to the sanctuary of the dressing room.
A tactical switch which saw Greg Halford switch to a central midfield position to track Ramirez helped change the balance of the game in the second half. Middlesbrough found chances harder to come by and were at last forced to defend. Halford and Kirk Broadfoot couldn’t quite direct headers and there were signs of anxiety among Boro’s large contingent of travelling supporters.
Jordan Rhodes and Stewart Downing were introduced to the action but they were floored and the New York Stadium erupted when sub Jonson Clarke-Harris raced clear and crossed for the unmarked Frecklington to drill into the roof of the net.
The only downside for the Millers was the late dismissal of Halford after receiving two yellow cards.
But, miraculous late blocks from Broadfoot, Smallwood and Joe Mattock made sure of the points.
It is the first time Rotherham have won three straight matches in the second tier since 2003.
Millers: Camp, Richardson (Kelly 25), Mattock, Broadfoot, Wood, Halford, Frecklington, Smallwood, Thomas (Clarke-Harris 75), Derbyshire, Best
Middlesbrough: Konstantopoulos, Nsue, Friend, Gibson, Fry, Forshaw, Clayton, Stuani (Downing 64), Ramirez, Adomah, Nugent (Rhodes 75)
Referee: P. Bankes
Attendance: 10,783 (2,623 visitors)