Cheltenham Town took another giant step towards League One safety with this hugely impressive victory at Boundary Park.
All the damage was done in the first half, with Kayode Odejayi and John Finnigan (above) handing the Robins an early two-goal cushion.
Oldham re-grouped and came back strongly after the break, but the work rate and commitment throughout the side was absolutely faultless to swat the considerable attacking threat that Oldham presented. Earlier in the season the Latics produced arguably the best performance against Cheltenham all season at Whaddon Road but this time they were prevented from getting their football flowing by a Cheltenham side playing with confidence and having now won four of their last eight games.
So Cheltenham opened up a four point gap between themselves and the trap door with their third away victory in the last four.
Robins manager John Ward named an unchanged starting line-up. The only change to the squad was on the bench where Adam Connolly replaced Dénes Rósa, who has now returned to Wolves after his one month loan spell.
The home side began in confident fashion with their two wide midfield players Paul Warne and Chris Taylor pushed right up against the Cheltenham full-backs.
Oldham passed the ball confidently in the opening stages but there was very little room to manouvre at either end of the field with defenders from both sides keeping things tight.
In fact, neither team had a shot at goal during the opening 20 minutes and Cheltenham won the only corner of this opening period. JJ Melligan took it but the ball in was dealt with comfortably by the Oldham back line.
However, all that changed in the 22nd minute when Steven Gillespie made a bright run through the middle and his shot cannoned off a defender for a throw-in.
Craig Armstrong took it and the Oldham defence made two attempts to head the ball clear under pressure from Cheltenham forwards. Spencer challenged on the second occasion, getting his head to the ball and it dropped just nicely for Kayode Odejayi, eight yards out. The big man kept a cool head to steer the ball beyond giant goalkeeper Les Pogliacomi for his 14th goal of the season.
Things got even better in the 30th minute when Cheltenham won another corner, needlessly given away by defender Will Haining's mis-directed back header.
Melligan took it, the ball flicked off a couple of heads at the near post and Pogliacomi ventured out to punch. Unfortunately for the big Austrilian stopper he was unable to get good distance on his clearance and John Finnigan arrived on the edge of the box with a first time lob shot that sailed over everyone in the box and into the net.
Oldham's first shot arrived in the 36th minute when midfielder Richie Wellens played a neat one-two with Chris Porter but lifted his shot from the edge of the area over the crossbar.
It was not a first half that the home team will remember with any fondness, their only other shot at goal being a long-range effort from Chris Taylor that flew a long way wide.
Having made a self-assured start to the game the play-off chasers seemed strangely lacking in confidence during the first half, while Cheltenham simply chased and worked all over the pitch to win the ball and get it forward quickly to Odejayi and Gillespie.
Oldham manager John Sheridan took the unusual step of replacing his goalkeeper at half-time, Pogliacomi having come in for some strong criticism from the home fans for a nervous first half performance.
His replacement Alan Blayney was called into action almost immediately when Latics defender Sean Gregan missed an attempted clearance leaving Odejayi with a run at goal.
Odejayi hit his shot low to the goalkeeper's left but Blayney got down well to make a useful save.
Cheltenham suddenly found themselves under the sort of pressure from the home side they had expected earlier in the game.
Michael Townsend made a superb interception on Chris Porter after Wellens had released him with a good pass into the area; then Gary McDonald headed just over the bar after a spell of intense pinball action around the Cheltenham penalty area.
McDonald shot wide from 15 yards shortly afterwards as the Robins tried manfully to stem the rising tide towards their goal.
Jerry Gill went into the book for a foul on Luigi Glombard and Cheltenham were forced to defend a series of corner kicks with everyone pressed into rearguard action.
Oldham were forced into another change just short of the hour mark when Chris Porter limped off to be replaced by Andy Liddell, who immediately formed a three man forward line with Warne and Glombard.
The home side won a free-kick in a dangerous position just outside the area right on the mid-point of the second half but Neal Eardley's quickly taken effort, aimed at catching the defence off guard, lacked accuracy and speared into the crowd behind the goal.
Scott Brown, who had handled confidently in goal despite receiving a couple of clatterings from the Oldham forwards at corners, went into the book for time wasting but it was his opposite number who again prevented a third Cheltenham goal 17 minutes from time.
Gillespie embarked upon a fine solo run that took him past three defenders but his shot, although carrying plenty of weight, was close enough to the goalkeeper for him to parry it away.
Oldham continued to press forward but time and again they were frustrated by Cheltenham's solid defensive organisation. Then, with two minutes to go, Odejayi sent Melligan clear with most of the Oldham team up field and again Blayney needed to make a fingertip save to keep the score at 2-0.
Gradually the home supporters began to file away from the ground as the 260 Robins followers, almost lost in a vast stand behind the goal, still managed to make themselves heard with some impressive vocal support.
OLDHAM ATHLETIC (4-4-2): Pogliacomi (Blayney 46); Eardley, Haining, Gregan, Aljofree (Edwards 70); Warne, McDonald, Wellens, Taylor; Porter (Liddell 59), Glombard. Subs not used: Rocastle, Roque
CHELTENHAM TOWN (4-4-2): Brown; Gill, Townsend, Duff, Armstrong; Melligan, Finnigan, Bird, Spencer; Odejayi, Gillespie (Connolly 90). Subs not used: Caines, Lowe, Reid, Connor
REFEREE: K.D. Hill (Hertfordshire)
ATTENDANCE: 5,426 (260 from Cheltenham)