Two late goals from Jonathan Benteke and Callum Lang secured the three points for Latics as Cheltenham Town striker Sam Jones saw red for a headbutt.
Latics started the game brightly with Jose Baxter dragging a shot wide only a couple of minutes into the game after some neat control and play from Dan Gardner.
Chris O’Grady then found Baxter running into the box, but Cheltenham Captain Johnny Mullins provided a vital interception to deny the Oldham man.
The visitors grew into the game and created their first chance as William Boyle headed wide from a Chris Hussey freekick.
The game seemed to be fizzling out as the half came to a close, but Latics stepped up a gear searching for the opening goal.
Tom Hamer produced a delightful cross field pass for Gevaro Nepomuceno who sat his man down before being denied by a good save from Scott Flinders in the Cheltenham goal.
From the resulting corner George Edmundson probably should have scored with a header, but he put it just wide of the post.
As the game entered stoppage time Jones produced a late challenge on Christopher Missilou with referee Ben Toner ready to give the Cheltenham striker a yellow card.
However, Jones and Baxter got into a heated exchange with The Robins man going for a headbutt in for Baxter giving referee Toner no choice but to brandish the red card and send Jones for an early shower.
Frankie Bunn introduced Ishmael Miller in the second half and he almost made an instant impact cutting in from the right-hand side, but he shot was blocked.
Nepomuceno tried his luck as he cut inside onto his left foot, but Flinders pushed the effort out for a corner with a decent save.
Latics finally took the lead through substitute Benteke as Rob Hunt crossed from down the left into the Oldham striker who was sliding in to open the scoring.
The home side never looked in trouble once they took the lead and Miller almost grabbed a second, but he could only fire his shot over from a corner.
Latics did have their second goal as the game was coming to an end when Lang picked up the ball on the edge of the box, took on three Cheltenham players a lovely bit of skill, before drilling the ball into the bottom corner.
Latics will be hoping to build on tonight’s victory when they travel to Northampton Town on Saturday afternoon.
Attendance 2865 (92 Away)
Iversen, Hamer, Clarke ©, Edmundson, Hunt, Lang, Missilou, Gardner, Nepomuceno, Baxter (Benteke 64’), O’Grady (Miller 54’)
Flinders, Hussey, Mullins ©, Atangana, Broom, Boyle, Maddox (Addai 82’), Jones, Clements (Barnett 66’), Alcock, Varney