On-the-whistle report: Millers on the charge ... MK Dons 0 Rotherham United 3

Michael Smith could have had a hat-trick in the first half. Picture by Jim Brailsford

The impressive Millers inflicted only a second home League One defeat on the Dons as they stretched their own unbeaten run to nine matches and recorded their eighth clean sheet.

They fully deserved the margin of their latest victory earned through a first-half Michael Ihiekwe header and second-half strikes from Dan Barlaser, direct from a corner, and Freddie Ladapo.

MK supporters were leaving the stadium well before the end as Rotherham bossed proceedings.

Paul Warne's side remained in fifth spot but are now only a point away from the top two.

In-form Michael Smith came close to his 11th goal of the campaign in the fourth minute, beating the offside and lobbing home goalkeeper Andrew Fisher only to see his effort bounce off the bar.

Soon afterwards, at the other end, Peter Kioso was only a whisker wide as he drove in from the right and unleashed a low, fizzing shot.

The Millers were the better side in the opening exchanges and on 13 minutes it looked as if another Ben Wiles 'special' was on the cards.

The midfielder shaped to shoot, just as he had to such spectacular effect at Bolton Wanderers last month, but this time his curling effort slipped the wrong side of the post.

Rotherham made the breakthrough in the 28th minute as Barlaser sent a pinpoint cross on to the head of Ihiekwe.

The centre-half still had plenty to do and, helped by Fisher's rush from goal, directed a looping header into an unguarded net

Well over 1,000 Millers fans had made the journey to Buckinghamshire and they were in fine voice in a magnificent but sparsely-populated stadium.

They were even louder in the 35th minute as Smith bore down on goal in a one-on-one until a heavy touch saw a golden opportunity go begging.

The Dons looked dangerous in attack but Rotherham's all-out press repeatedly sent the home team backwards.

Millers boss Warne found himself on the wrong end of a yellow card issued by referee Christopher Sarginson, the first caution of his near-five-year managerial career.

As half-time approached, David Kasumu's well-struck shot for the Dons was deflected for a corner and Smith was close to making it 2-0 with a back-post header from Shane Ferguson's cross.

Rotherham were attacking well and defending with discipline, although Zak Jules spurned a big chance to equalise when he headed over.

The Millers deserved their lead and should really have been even further in front as they headed in at the break.

Warne had rested skipper Richard Wood after his leg knock against Wycombe Wanderers in midweek, putting him on the bench and bringing in Ihiekwe in the centre of a three-man rearguard.

Josh Vickers retained his place in the net after an impressive Millers league debut versus the Chairboys when regular number one Viktor Johansson was missing because of a back spasm.

Rotherham continued in the same vein after the interval and six minutes into the second half Ihiekwe rose and headed Ferguson's corner towards goal only to be thwarted by Fisher's save.

Six minutes after the hour mark, the Millers doubled their avantage as Barlaser's corner appeared to beat everyone to nestle in the net to the side of which the boisterous Millers faithful were gathered.

Wes Harding might have made it three before subsitute Ladapo was on hand in the 72nd minute to do just that, shooting low past Fisher to end the contest.

The margin of victory didn't flatter Rotherham at all.

MK Dons (3-4-3): Andrew Fisher; Warren O'Hora, Harry Darling, Dean Lewington; Peter Kioso, Matt O'Riley, David Kasumu, Zak Jules (Tennai Watson 60); Hiram Boateng (Troy Parrott 63), Mo Eisa, Scott Twine. Subs not used: Franco Ravizzoli, Josh Martin, Aden Baldwin, Josh McEachran, Max Watters.

Rotherham (3-5-2): Josh Vickers; Rarmani Edmonds-Green, Michael Ihiekwe, Wes Harding; Chiedozie Ogbene, Ben Wiles, Dan Barlaser (Hakeem Odoffin 82), Ollie Rathbone, Shane Ferguson (Mickel Miller 71); Will Grigg (Freddie Ladapo 63), Michael Smith. Subs not used: Viktor Johansson, Richard Wood, Kieran Sadlier, Josh Kayode.

Goals: Ihiekwe 27, Barlaser 66, Ladapo 73 (Rotherham).

Referee: Christopher Sarginson (Staffordshire).

Attendance: 8,448 (1,242).