MK Dons fell to their third defeat of the season as fellow promotion chasers Sheffield United condemned them to a 2-1 defeat at Bramall Lane on Tuesday night.
Stephen Gleeson's first goal of the campaign cancelled out Richard Cresswell's first-half strike but United found what proved to be the winner when Matt Phillips converted from six-yards.
Any hopes of gaining at least a point from the game were all but dashed for the Dons six minutes from time when Adam Smith was dismissed for his second caution.
Heading into the game it was a battle of fifth versus sixth in League 1, however, the defeat pushed the Dons down to seventh while United climb to fourth.
The Dons, on the back of four draws in their last six games, opted for a change in formations as the switched from their trusted 4-2-3-1 to a 4-3-3 with Dean Bowditch, Jabo Ibehre and Luke Chadwick forming the role of an attacking three.
The starting 11 included three changes to the side that were involved in the stalemate with Scunthorpe three days earlier. Ibehre took the place of Clinton Morrison, who returned to parent club Sheffield Wednesday but was supporting the Dons from the Bramall Lane stands, while Tom Flanagan stepped into defence alongside Mark Beevers as cover for the injured Gary MacKenzie and Shaun Williams in for Angelo Balanta.
The early phases at Bramall Lane hinted at an evenly matched contest ahead with good movement from both sides and although openings were created there was little in the way of goal mouth action.
Blades' Billy Clarke was the first to call a save in the game in the sixth minute when he cut inside from the left to drive a shot, which picked up a deflection on Flanagan, into the grateful arms of David Martin.
A great opportunity to open the scoring came to the Dons soon after when Williams escaped through to the left of the box, but a casual flick by Ibehre fell inches wide, and when Luke Chadwick slipped Gleeson through to goal the midfielder had his close-range shot well blocked by Marcus Williams.
With only 11 minutes on the clock the Dons were left holding their breath when Martin, some 15-yards out of the box, cleared the ball but in the meantime Smith had brought down Stephen Quinn. The right-back picked up a caution for his challenge, although the home crowd disagreed with the referee's punishment.
When the Blades surged forwards the noise rose at Bramall Lane and the pressure was on to start firing at the Dons' goal which is exactly what Marcus Williams opted to do. His first shot, a ferocious one from the edge of the box, was blocked before he blazed over the follow up. Although off-target, his efforts were well received by the crowd.
In the 22nd minute Sheffield United broke the dead lock when Quinn and Billy Clarke combined before the latter played a defence splitting through ball into the path of Cresswell. The striker eased past Smith and Flanagan before applying the finishing touch past Martin.
The Dons goalkeeper kept the deficit to one when Cresswell was again allowed to run freely, this time arriving in time to connect with a delivery that had been cut back from the byline, and Martin did well after an initial fumble to keep hold of the first-time shot.
Having been in a strong position in terms of possession, the Dons found the momentum was with the home side and Robinson's men had to re-gather their composure to prevent the Blades from bossing the game.
United were resolute in defence with the midfield quick to offer support at the back to cut out the Dons' breaks into their final third. The Dons struggled to make the most of their usual passing games as they were quickly pressed on the ball by the Blades and afforded little time on the ball.
The Dons started the second half much brighter, finding more time on the ball and enjoying possession outside their half.
Seven minutes after the interval the Dons were rewarded with their positive re-start when a quick break saw some good play from Dean Bowditch, who fed the ball to Ibehre. The front man did well to hold off the Blades markers as he retained the ball and played a crisp pass at the feet of Gleeson, the Irish midfielder took a touch before emphatically converting into the bottom corner.
United introduced Ched Evans in place of goal scorer Cresswell to inject a fresh threat in front of goal. The Welsh international striker could have had an immediate impact when Clarke's sharp pass was played into the box, but Flanagan managed to stab the ball away before Evans could convert.
However, the young Dons defender didn't have the same success moments later when Clarke got thr better of him, turning inside to whipped a cross in for Phillips to turn home.
In a bid to get back into the game, for the second time, the Dons made a triple substitution to boost their attack with Angelo Balanta, Daniel Powell and Charlie MacDonald all aiming to make an impact in the closing stages.
They certainly gave the Dons some impetus as the visitors dragged the United defence apart with an impressive tally of passes, but when Balanta, after a one-two with Potter, drilled through a crowded box George Long was equal to the shot.
The Dons' task became even harder with six minutes remaining when Smith's trip in substitute Ryan Flynn earned him his second caution and the Dons were forced to see out the game with 10 men.
Despite the numerical disadvantage the Dons maintained their hunt for a goal that would earn them a point, even Martin was brought forward for set plays but time ran out and Dons were forced to head back down the M1 with nothing to show for their evening's efforts.
Sheffield United (4-4-2): Long; Lowton, Collins, Maguire, M Williams; Phillips, McDonald (Doyle 82), Montgomery (c), Quinn; Cresswell (Evans 63), Clarke (Flynn 76
Subs unused: Simonsen, Jean-Francois.
Booked: Cresswell, Phillips
Goals: Cresswell 22, Phillips 67
MK Dons (4-3-3): Martin; Smith, Flanagan, Beevers, Lewington (c); S Williams (Balanta 70), Potter, Gleeson; Chadwick, Ibehre (MacDonald 70), Bowditch (Powell 70).
Subs unused: Chicksen, McNamee.
Booked: Smith, Balanta
Sent-off: Smith 84
Goal: Gleeson 52
Referee: Graham Sailsbury (Lancashire)