Latics suffered a 3-1 defeat in their final pre-season game against League Two side Carlisle United.
Substitute Rhys Murphy had pulled a goal back in the second half but goals from Angelo Balanta, Derek Asamoah and Steven Rigg won the game for the Cumbrians.
It could have been worse for Latics but Danny Grainger smashed his first half penalty wide of the goal.
Latics kept possession well in the opening stages of the first half without really penetrating the Carlisle defence.
The home side had a golden opportunity to take the lead on 13 minutes as the referee awarded them a penalty kick.
Trialist Fraser Kerr brought down Asamoah in the box but Grainger smashed his penalty wide of David Cornell’s goal.
The Cumbrians were in the ascendancy and Jason Kennedy’s strike from 25 yards went inches over Cornell’s goal.
Latics did manage their first shot on goal on 17 minutes but Carlisle goalkeeper Mark Gillespie held the ball well.
Just after the midway point in the first half, Latics should have taken he lead through Jake Cassidy.
Winchester’s inch-perfect cross found Lee Croft on the right-hand side. He controlled and crossed for Cassidy six yards out, but his header skimmed the top of the crossbar and went over.
Carlisle United took the lead just before the half hour mark through Balanta.
A corner was cleared on to the edge of the box where Balanta stood. The forward struck and it found a way past Cornell courtesy of a deflection of a Latics player.
Asamoah almost doubled their lead two minutes later but Gavin Gunning managed to get a block on the ball at the final second.
Latics needed a spark and five minutes from the break, they almost found an equaliser.
Croft received Winchester’s through ball out wide, he cut inside and fired goalwards but Gillespie pulled off a neat save to deny the winger.
With the first half almost up, Jones’ cross into the box was headed goalwards by Jonathan Forte but again the goalkeeper saved well.
Latics started the second half brightly and should have been awarded a penalty on 54 minutes.
Winchester looked to be nicked inside the penalty area, every single Latics player appealed but the referee waved play on.
That would come to cost Latics as they fell two goals two minutes later.
Carlisle broke up field, and a cross into the box found the onrushing Asamoah who headed the ball over Cornell and Antony Sweeney made sure at the back post.
Darren Kelly made a double substitution on 64 minutes bringing on Dominic Poleon and Murphy and two minutes later the two combined to pull a goal back for Latics.
Poleon received the ball in the box, smartly turned his opponent and crossed for the onrushing Murphy to power past the goalkeeper to reduce the arrears.
Latics started to up the tempo with Poleon testing goalkeeper Gillespie from 25 yards whilst Joesph Mills’ effort was blocked at the last with 15 minutes on the clock remaining.
George Green was introduced into the action and almost made an instant impact.
The midfielder’s free kick on the right hand side with only 10 minutes remaining was punched by the goalkeeper but no Latics player followed up the chance.
Carlisle regained their two goal advantage on 84 minutes through Rigg. The midfielder found space at the back post and planted his header past Cornell to make it 3-1.
Latics had two fantastic opportunities to get back into the game in the dying minutes of the game.
Firstly, Poleon’s free header from six yards was tame and the goalkeeper saved comfortably. Minutes afterwards, Murphy raced past the goalkeeper but stumbled at the final second and the chance passed.
Carlisle United: Gillespie, Miller, Atkinson, Raynes, Grainger, Brough, Kennedy, Joyce, Balanta, Asamoah, Osei
Subs: Hanford, Wyke, Hery, Sweeney, Ibehre, Meppen-Walter, Dicker, Kearns, Archibald-Henville, Rigg, Walker, Hammell, Thompson.
Oldham Athletic: Cornell, B.Wilson, Gunning, Kerr, Mills, Kelly, Jones, Winchester (Green 79’), Croft, Forte (Murphy 64’), Cassidy (Poleon 64’).
Subs not used: Coleman, Brown, Edmundson, Dieng, Philliskirk, Hiwat, Turner.
Goals: Carlisle United (Balanta 29’, Asamoah 56’, Rigg 84’) 3-1 Oldham Athletic (Murphy 66’)