Substitute Garry Thompson scored a second-half winner for Scunthorpe at Oldham as both sides ended with 10 men.
David Mirfin's opened the scoring for the visitors in the 73rd minute, heading in Josh Walker's corner.
Filipe Morais levelled as his right-wing cross sailed over Sam Slocombe's head and in off the post.
Thompson won the game with a header from Walker's cross and the latter was sent off, along with Oldham's Keanu Marsh-Brown.
Marsh-Brown received a straight red card for his two-footed lunge on Walker, whose angry reaction earned him a second booking.
VIEWS FROM THE DRESSING ROOM
Oldham Athletic manager Paul Dickov told BBC Radio Manchester:
"We're really disappointed in how we lost the game, I felt we thoroughly deserved to win it.
"The first 70 minutes I thought we were excellent, as good as we've been since I've been here.
"We need to take the positives out of the game tonight because I thought there were a lot of them.
"Throughout the team we got a little bit anxious when we got on top, we started forcing things which is what I think cost us."
Scunthorpe United manager Alan Knill told BBC Radio Humberside:
"It was a battling performance, we kind of rode our luck but the good thing is we kept going and kept believing in what we can do and got the two goals.
"We've been on the end of a lot of games like that where we've been the team that's hit the post or hit the bar and had lots of chances and come away losing. It feels good to come away with three points because it was quite a tough game.
"Everytime we put the ball in their box we looked dangerous, especially set plays.
"Anybody who thought it was going to be an easy game was definitely wrong."
Live Text Commentary
Full Time The referee signals the end of the game.90:00 +5:36
Unfair challenge on Jon Parkin by Jean Yves Mvoto results in a free kick. Jon Parkin takes the free kick.90:00 +3:26
Reuben Reid takes a shot. Save by Sam Slocombe. Inswinging corner taken right-footed by Filipe Morais from the right by-line, David Mirfin makes a clearance.90:00 +2:25
James Tarkowski sends in a cross, Christian Ribeiro manages to make a clearance.90:00 +0:45 Substitution
Substitution Eddie Nolan comes on in place of Mark Duffy.90:00 +0:45
Effort on goal by Shefki Kuqi from inside the area goes harmlessly over the bar.90:00 +0:18
The ball is sent over by Christian Ribeiro, Jon Parkin takes a shot. Alex Cisak makes a save.88:35 Dismissal
Dismissal The referee shows Josh Walker a red card for second bookable offence.87:13
Paul Reid takes the free kick.87:13 Booking
Booking The referee shows Garry Thompson a yellow card.86:52 Dismissal
Dismissal Keanu Marsh-Brown receives a red card.86:37
Foul by Keanu Marsh-Brown on Josh Walker, free kick awarded.84:57
The ball is delivered by Keanu Marsh-Brown.84:29
The official flags Jon Parkin offside. James Tarkowski takes the free kick.83:48
Free kick awarded for a foul by Andy Barcham on Shefki Kuqi. Alex Cisak takes the free kick.83:35
Effort from 25 yards by Mark Duffy. Reece Brown gets a block in.82:58
Corner taken by Josh Walker, Jean Yves Mvoto makes a clearance.82:11
Keanu Marsh-Brown challenges Mark Duffy unfairly and gives away a free kick. Josh Walker crosses the ball in from the free kick, Shefki Kuqi makes a clearance.81:55
The ball is sent over by Christian Ribeiro, Filipe Morais gets a block in.80:57 Substitution
Substitution Matt Smith comes on in place of David Mellor.
Garry Thompson gives away a free kick for an unfair challenge on Kieran Lee. The free kick is swung in left-footed by David Mellor, clearance made by David Mirfin.79:07
Assist on the goal came from Josh Walker.79:07 Goal scored
Goal! - Garry Thompson - Oldham 1 - 2 Scunthorpe Garry Thompson finds the back of the net with a headed goal from deep inside the penalty box. Oldham 1-2 Scunthorpe.78:58
The ball is sent over by David Mirfin, Jean Yves Mvoto makes a clearance.78:11
Foul by Filipe Morais on Christian Ribeiro, free kick awarded. Free kick crossed by Josh Walker, clearance made by Kieran Lee.77:03 Goal scored
Goal! - Filipe Morais - Oldham 1 - 1 Scunthorpe Filipe Morais scores from his cross. Oldham 1-1 Scunthorpe.76:08
Corner from the right by-line taken by Filipe Morais, clearance made by Jamie Reckord.73:38 Substitution
Substitution (Scunthorpe) makes a substitution, with Garry Thompson coming on for Jimmy Ryan.73:38 Substitution
Substitution Chris Taylor leaves the field to be replaced by Reuben Reid.72:53
The assist for the goal came from Josh Walker.72:53 Goal scored
Goal! - David Mirfin - Oldham 0 - 1 Scunthorpe David Mirfin grabs a headed goal from inside the penalty area. Oldham 0-1 Scunthorpe.72:34
Inswinging corner taken by Josh Walker from the left by-line,72:03
A cross is delivered by Andy Barcham, Reece Brown gets a block in. Jon Parkin takes a shot. Blocked by Kieran Lee.71:05
The ball is sent over by Tom Adeyemi, Sam Slocombe makes a save. Outswinging corner taken by Filipe Morais from the right by-line played to the near post, clearance made by Paul Reid.68:21
A cross is delivered by Jon Parkin, Andy Barcham takes a shot. Comfortable save by Alex Cisak.65:50
Damien Mozika gives away a free kick for an unfair challenge on Tom Adeyemi. David Mellor delivers the ball from the free kick left-footed from left channel.65:14
Shefki Kuqi delivers the ball, Josh Walker makes a clearance.64:52
Centre by Filipe Morais, clearance made by David Mirfin.63:58
The ball is delivered by Jon Parkin, clearance by James Tarkowski.62:28
Jon Parkin produces a cross, clearance by Jean Yves Mvoto.61:34
Free kick awarded for an unfair challenge on Josh Walker by Keanu Marsh-Brown. Paul Reid takes the direct free kick.60:11
The free kick is swung in right-footed by Josh Walker.60:11 Booking
Booking Booking for Reece Brown for unsporting behaviour.59:59
Free kick awarded for an unfair challenge on Christian Ribeiro by Reece Brown.59:34
Jamie Reckord crosses the ball.58:17
Keanu Marsh-Brown crosses the ball. The assistant referee signals for offside against Filipe Morais. Sam Slocombe restarts play with the free kick.57:38
The ball is delivered by Jimmy Ryan.55:42
The ball is sent over by Chris Taylor.52:09
Reece Brown sends in a cross, clearance by Paul Reid.51:52
Reece Brown produces a cross, save made by Sam Slocombe.51:03
Mark Duffy concedes a free kick for a foul on Keanu Marsh-Brown. Free kick crossed right-footed by Filipe Morais from left wing, Josh Walker makes a clearance.50:45
Filipe Morais produces a cross, Paul Reid makes a clearance.49:24
A cross is delivered by Filipe Morais.48:42
Keanu Marsh-Brown delivers the ball, Effort from deep inside the box by Filipe Morais hits the post.48:08
Keanu Marsh-Brown takes a shot. Save made by Sam Slocombe.47:12
Christian Ribeiro crosses the ball.46:06
The ball is sent over by Chris Taylor.45:01
The game restarts for the second half.45:00 +1:00 Half time
Half Time The ref blows to end the first period.45:00 +0:26 Booking
Booking Jamie Reckord goes into the referee's book for unsporting behaviour.42:25
A cross is delivered by Christian Ribeiro, Jon Parkin takes a shot. Jean Yves Mvoto gets a block in. Corner taken by Josh Walker played to the near post, Andy Barcham gives away a free kick for an unfair challenge on Alex Cisak. Alex Cisak takes the free kick.41:45
The ball is crossed by Kieran Lee, Tom Adeyemi takes a shot. Save by Sam Slocombe.40:02
Handball decision goes against Keanu Marsh-Brown. David Mirfin takes the free kick.39:44
The ball is crossed by Jimmy Ryan, save made by Alex Cisak.37:11
Paul Reid challenges Tom Adeyemi unfairly and gives away a free kick. Free kick crossed by Filipe Morais, clearance by Jamie Reckord.36:35
Jon Parkin gives away a free kick for an unfair challenge on Filipe Morais. Direct free kick taken by James Tarkowski.35:57
Centre by Filipe Morais, Shot on goal by Shefki Kuqi from just inside the area clears the crossbar.35:37
Mark Duffy sends in a cross, Alex Cisak makes a save.34:49
Handball by Mark Duffy. Direct free kick taken by Alex Cisak.33:00
Filipe Morais takes a outswinging corner from the right by-line played to the near post.31:37
Direct free kick taken by James Tarkowski.31:37 Booking
Booking Josh Walker booked.31:31
Kieran Lee fouled by Josh Walker, the ref awards a free kick.31:01
David Mellor delivers the ball, save by Sam Slocombe.29:50
Corner taken by Josh Walker from the left by-line, David Mirfin has a headed effort at goal from deep inside the area missing to the right of the target.29:40
Andy Barcham sends in a cross, clearance made by Jean Yves Mvoto.28:15
Centre by Keanu Marsh-Brown.25:54
Keanu Marsh-Brown is ruled offside. Sam Slocombe restarts play with the free kick.24:31
Jean Yves Mvoto gives away a free kick for an unfair challenge on Jimmy Ryan. The free kick is swung in right-footed by Josh Walker, Reece Brown manages to make a clearance.23:36
Free kick awarded for a foul by Jamie Reckord on Shefki Kuqi. James Tarkowski restarts play with the free kick.21:59
Centre by Keanu Marsh-Brown, Paul Reid gets a block in. Corner taken by Filipe Morais from the right by-line, Shot by Shefki Kuqi. Sam Slocombe makes a save.20:50
Corner taken by Filipe Morais played to the near post, Josh Walker makes a clearance.20:07
Free kick awarded for an unfair challenge on Keanu Marsh-Brown by Paul Reid. Filipe Morais delivers the ball from the free kick right-footed from right wing, clearance made by Jamie Reckord.19:40
Effort from 20 yards by Jon Parkin. Save by Alex Cisak.18:11
Shot from 25 yards by Filipe Morais. Save by Sam Slocombe.16:08
Inswinging corner taken by Josh Walker from the left by-line, Alex Cisak makes a save.15:44
The ball is swung over by Damien Mozika, Kieran Lee gets a block in. Josh Walker takes a short corner.14:29
Jimmy Ryan crosses the ball, Jon Parkin takes a shot. Alex Cisak makes a save. Corner taken right-footed by Josh Walker from the left by-line, Reece Brown makes a clearance. Corner from the left by-line taken by Josh Walker, clearance made by Shefki Kuqi.13:09
The ball is delivered by Jimmy Ryan.11:24
Shefki Kuqi challenges Josh Walker unfairly and gives away a free kick. Free kick taken by Paul Reid.9:08
The ball is crossed by Chris Taylor.6:05
The ball is delivered by Kieran Lee, blocked by Jamie Reckord. Corner taken by Filipe Morais, Jimmy Ryan manages to make a clearance.3:25
Effort on goal by Keanu Marsh-Brown from 20 yards. David Mirfin gets a block in.2:28
A cross is delivered by Christian Ribeiro, save made by Alex Cisak.2:04
Jimmy Ryan delivers the ball.1:42
Chris Taylor delivers the ball, comfortable save by Sam Slocombe.1:24
Handball decision goes against Jon Parkin. Free kick taken by James Tarkowski.0:51
Shefki Kuqi challenges David Mirfin unfairly and gives away a free kick. Direct free kick taken by Sam Slocombe.0:27
Jon Parkin concedes a free kick for a foul on Jean Yves Mvoto. Alex Cisak takes the free kick.0:00
The ref blows the whistle to start the match.
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