Sheffield United maintained their automatic League One promotion bid with second-half goals from Michael Doyle and Dave Kitson at Oldham.
The Blades went in front on 57 minutes when Dominic Poleon's shot was half-saved by Alex Cisak, only for Doyle to put away the rebound from 12 yards.
Oldham almost levelled when Matt Smith headed Lee Croft's cross inches wide before his 18-yard shot was saved.
But United sealed the points late on with Kitson's 10th goal of the season.
Cisak charged off his line and failed to gather Tony McMahon's free-kick, giving Kitson the chance to head into an empty net from 14 yards.
The Blades' sixth game without defeat, to cap boss Danny Wilson's 100th game in charge, keeps them within a point of leaders Doncaster Rovers and two ahead of Swindon Town on a day when all the top three won.
But, in the week when they also exited the FA Cup, managerless Oldham's first defeat in four league games plunges them back into the bottom four.
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Oldham caretaker manager Tony Philliskirk told BBC Radio Manchester:
"There was nothing between the teams on today, but two individual errors have cost us the game.
"We know that we've got a massive game next week at Tranmere, but it's in our hands.
"It's disappointing to drop back into the bottom four, but it's going to be nip and tuck for the rest of the season. The sooner we get those wins, the better."
Sheffield United first-team coach Chris Morgan told BBC Radio Sheffield:
"It's a great result for us, coming away from home against Oldham, who have done fantastically well over the last couple of weeks.
"They've got a lot of confidence from the games against Liverpool and the two games against Everton.
"We knew it was going to be tough. It's never an easy place to come, and at half time we just said keep going, keep the shape, be resilient and we knew we'd get a chance.
"The chance came and when you get them you've got to take them."
"So really pleased to come away and get another win."
Live Text Commentary
Full Time The referee blows his whistle to end the game.90:00 +3:36
Foul by Dave Kitson on Dean Furman, free kick awarded. James Tarkowski restarts play with the free kick.90:00 +2:26
The referee penalises Chris Iwelumo for handball. Matthew Hill takes the direct free kick.90:00 +1:09
Corner taken short by Kevin McDonald.90:00 +0:47
Effort from the edge of the penalty box by Michael Doyle goes wide of the right-hand upright.90:00 +0:23
Corner from right by-line taken by Jonathan Grounds.90:00 +0:02
Matt Smith takes a shot.87:22
Corner taken right-footed by Jose Baxter to the near post, James Tarkowski produces a right-footed shot from close in that clears the bar.86:24 Booking
Booking Dave Kitson receives a yellow card for leaving the field of play without the referee's permission.85:17
The assist for the goal came from Tony McMahon.85:17 Goal scored
Goal! - Dave Kitson - Oldham 0 - 2 Sheff Utd Dave Kitson finds the back of the net with a headed goal from just inside the box. Oldham 0-2 Sheff Utd.84:42
Free kick awarded for a foul by Jean Yves Mvoto on Dave Kitson. Tony McMahon restarts play with the free kick.84:13
Jordan Obita gives away a free kick for an unfair challenge on Tony McMahon. George Long restarts play with the free kick.83:37
Barry Robson gives away a free kick for an unfair challenge on Jose Baxter. Alex Cisak takes the direct free kick.82:45
Neill Collins takes a shot. Clearance by Dean Furman.82:14
Free kick crossed by Barry Robson.82:14 Booking
Booking Caution for Jose Baxter.82:04
Free kick awarded for an unfair challenge on Ryan Flynn by Jose Baxter.81:43
Inswinging corner taken from the right by-line by Jonathan Grounds.81:15
Matt Smith takes a shot. Save by George Long.
Outswinging corner taken left-footed by Barry Robson, Headed effort on goal by Harry Maguire from just inside the box goes harmlessly over the goal.79:01
Matt Smith gives away a free kick for an unfair challenge on Harry Maguire. Free kick taken by George Long.77:56
James Tarkowski fouled by Dave Kitson, the ref awards a free kick. Direct free kick taken by James Tarkowski.77:16 Substitution
Substitution Chris Iwelumo is brought on as a substitute for Connor Brown.76:35
Jose Baxter fouled by Kevin McDonald, the ref awards a free kick. Jose Baxter takes the free kick.74:51
Matt Smith takes a shot.73:04
Free kick taken by Alex Cisak.73:04 Booking
Booking Booking for Kevin McDonald for unsporting behaviour.72:53
Free kick awarded for an unfair challenge on Jose Baxter by Kevin McDonald.72:09
Unfair challenge on Tony McMahon by Jordan Obita results in a free kick. Free kick taken by George Long.70:58 Substitution
Substitution Callum McFadzean replaces Dominic Poleon.68:42
Lee Croft produces a cross, clearance by Kevin McDonald.67:28
Corner from right by-line taken by Jose Baxter.67:02
Connor Brown delivers the ball.64:50
Matt Smith is adjudged to have handled the ball. Free kick taken by Harry Maguire.63:45
Free kick taken by George Long.63:45 Substitution
Substitution James Wesolowski leaves the field to be replaced by Jordan Obita.63:45
The referee blows for offside against Matt Smith.60:10
Dean Furman gives away a free kick for an unfair challenge on Harry Maguire. Free kick taken by George Long.59:54
Jonathan Grounds takes a inswinging corner.59:37
James Wesolowski takes a shot.59:02
Dominic Poleon has an effort at goal from outside the penalty box which goes wide right of the target.56:50
The assist for the goal came from Dominic Poleon.56:50 Goal scored
Goal! - Michael Doyle - Oldham 0 - 1 Sheff Utd Michael Doyle grabs a goal from the edge of the area to the bottom left corner of the goal. Oldham 0-1 Sheff Utd.56:22
Dominic Poleon takes a shot.52:59
Free kick awarded for an unfair challenge on Matt Smith by Matthew Hill. Jose Baxter takes the direct free kick.52:36
Handball by Barry Robson. Alex Cisak restarts play with the free kick.51:31
Robbie Simpson produces a cross, George Long makes a save.45:01
The match restarts for the second half.45:00 +2:44 Half time
Half Time It is the end of the first-half.45:00 +2:09
Shot from just outside the area by Jose Baxter goes over the bar.44:40
Corner taken left-footed by Barry Robson from the right by-line, Connor Brown makes a clearance.44:19
Tony McMahon takes a shot. Clearance made by James Tarkowski.38:16
The official flags Barry Robson offside. Alex Cisak restarts play with the free kick.37:44
James Tarkowski gives away a free kick for an unfair challenge on Michael Doyle. Direct free kick taken by Neill Collins.35:51
Barry Robson takes a short corner.34:42
Barry Robson crosses the ball from the free kick left-footed from right channel.34:42 Booking
Booking Robbie Simpson receives a yellow card.34:30
Free kick awarded for a foul by Robbie Simpson on Tony McMahon.33:17
Free kick awarded for an unfair challenge on James Wesolowski by Dave Kitson. Jonathan Grounds takes the direct free kick.32:23
Direct free kick taken by Jose Baxter.32:23 Booking
Booking Michael Doyle is given a yellow card.32:02
Michael Doyle challenges James Wesolowski unfairly and gives away a free kick.29:20
Free kick awarded for a foul by Michael Doyle on Jose Baxter. Jose Baxter has a direct shot on goal from the free kick.28:59
Foul by Kevin McDonald on James Wesolowski, free kick awarded. Lee Croft takes the free kick.26:17
Jose Baxter has an effort at goal from outside the area missing to the wide right of the goal.25:30
Michael Doyle concedes a free kick for a foul on Lee Croft. Free kick crossed right-footed by Jose Baxter.24:25
Free kick awarded for a foul by Jean Yves Mvoto on Dave Kitson. Harry Maguire takes the direct free kick.24:00
The assistant referee flags for offside against Matt Smith. George Long takes the direct free kick.22:24
Corner taken by Barry Robson from the left by-line, Harry Maguire takes a shot.22:12
The ball is swung over by Michael Doyle.21:36
Foul by James Tarkowski on Dave Kitson, free kick awarded. Michael Doyle takes the free kick.19:32
Corner from right by-line taken by Jose Baxter.19:21
Lee Croft produces a cross.18:59
Robbie Simpson takes a shot. Harry Maguire gets a block in.17:32
Free kick taken by Matthew Hill.17:32 Booking
Booking Jean Yves Mvoto receives a yellow card for unsporting behaviour.17:14
Jean Yves Mvoto concedes a free kick for a foul on Barry Robson.14:51
Free kick awarded for a foul by Dominic Poleon on Connor Brown. Direct free kick taken by Alex Cisak.14:20
James Wesolowski takes a shot. Clearance by Matthew Hill.13:30
Matt Smith concedes a free kick for a foul on George Long. George Long takes the free kick.13:07
Inswinging corner taken by Jonathan Grounds, Kevin McDonald manages to make a clearance.12:38
Corner taken by Jose Baxter, save by George Long.11:44
Dominic Poleon challenges Connor Brown unfairly and gives away a free kick. Jose Baxter delivers the ball from the free kick right-footed from right channel, clearance made by Harry Maguire.10:15
Ryan Flynn fouled by James Wesolowski, the ref awards a free kick. Tony McMahon produces a shot on goal direct from the free kick.9:13
Jonathan Grounds takes a inswinging corner to the near post.9:00
Jose Baxter delivers the ball, clearance by Harry Maguire.7:55
James Wesolowski challenges Ryan Flynn unfairly and gives away a free kick. Free kick taken by Tony McMahon.7:37
Matt Smith takes a shot. Harry Maguire gets a block in.5:48
Free kick awarded for an unfair challenge on Matthew Hill by Lee Croft. The free kick is swung in left-footed by Barry Robson, Dean Furman makes a clearance.4:47
Corner taken by Barry Robson from the left by-line to the near post, Jonathan Grounds makes a clearance.4:32
The ball is sent over by Ryan Flynn.3:19
Michael Doyle takes a shot. Clearance made by Kevin McDonald.2:09
Shot from just outside the area by Jose Baxter misses to the right of the target.0:00
The match has kicked off.
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