Anthony Gerrard’s first-half header was the difference on a difficult night for MK Dons at SportsDirect.com Park.
The Latics captain headed his side in front just before half-time and despite seeing the ball for long periods of the contest, Dan Micciche’s men were unable to break down their opponents in tough conditions and earn themselves a share of the spoils.
Tuesday’s result leaves the Dons 22nd in the Sky Bet League One table, six points adrift of safety although still with those two games in hand.
Chuks Aneke returned to the action following his three-game absence due to suspension. He was one of three new additions to the starting XI along with Robbie Muirhead and Ethan Ebanks-Landell.
Ebanks-Landell got in the way of an early chance for Oldham but it was Aneke who produced the first shot on target in the sixth minute, forcing a save out of Johny Placide with a right-footed shot inside the area.
Soon after, Aneke set up Muirhead, who curled an effort just wide of the left upright from the edge of the D.
Aneke was looking bright early on but in the 12th minute he went down with a non-contact injury - an injury which forced him off two minutes later. He was replaced by Kieran Agard.
The blow didn’t stop the Dons threatening the Oldham goal and a superb pass from Josh Tymon almost created an opening for George Williams inside the Latics box but Placide was able to claim at his feet.
Scott Wootton then went close with a header into the side netting after Placide got caught underneath a well-taken Muirhead free-kick.
Lee Nicholls was called into for the first time on 18 minutes, getting down to his right to palm away a drive from Ben Pringle. The loose ball fell to Craig Davies but he dragged his left-footed shot wide of the target.
The hosts then had a goal chalked off by the linesman - Kryan Bryan the man in an offside position when he headed in from Pringle’s free-kick.
Micciche’s men went straight on the attack after the resulting free-kick was taken and Ugbo had a goal-bound shot blocked. Moments later, Williams got free down the right and crossed for Agard who, after taking a touch, saw the ball cleared away off his toes by a defender.
On the half-hour mark, the Dons had a decent appeal for a penalty waved away by referee Tom Nield. Upson was the man who appeared to be fouled in the area but, instead of seeing his side awarded a spot-kick, he was booked for simulation by the official.
Despite having the better of the chances in the first half, it was Oldham who went into the break with the lead after captain Anthony Gerrard powered in a header from a corner on 41 minutes. 1-0.
The Latics went close to doubling their lead within a minute of the re-start but Duckens Nazon’s deflected attempt landed on the roof of the net. Dan Gardner then shot wide after the Dons failed to properly clear the resulting corner.
On 52 minutes, the Dons threatened with a free-kick delivered into the area by Muirhead. Ebanks-Landell got a touch to the ball in before Cisse hooked an effort over the crossbar.
Micciche introduced Tavenier on the hour and he was immediately involved, sending in a cross which was claimed by Placide just in front of a lurking Agard. Agard then broke into the Oldham area but was dispossessed by Bryan as he looked to cut back and pull the trigger.
The Dons pushed for an equaliser and Aidan Nesbitt was brought on to add to that threat. However he, nor his teammates, here able to trouble Placide in the closing stages resulting in a disheartening defeat.
Starting XI: Nicholls; Ebanks-Landell, Wootton (Nesbitt 82), Lewington (c); Williams, Upson (Tavernier 61), Cisse, Tymon; Muirhead, Ugbo; Aneke (Agard 14).
Unused subs: Sietsma, Brittain, Ward, McGrandles, Nesbitt.
Booked: Upson, Nesbitt, Ebanks-Landell.
Attendance: 3,381 (119 away)
Referee: T Nield