Harkins has his say in Latics win
Gary Harkins scored the only goal of the game as Oldham earned a vital victory against Gillingham.
The three points gives the Latics breathing space above the League One relegation zone and punished the Gills for their wasteful finishing.
The visitors carved out two early openings as Joe Pigott headed straight at goalkeeper Mark Oxley before Chris Whelpdale fired off target.
Gillingham missed a glorious chance on the half-hour when Myles Weston, an early substitute for the injured Whelpdale, ran clean through on goal but was denied by Oxley.
Oldham went ahead after 33 minutes as David Worrall's deep cross found Harkins, who cracked a powerful shot inside the far post from eight yards out.
Jon Stead hit the post with an effort from the edge of the box as the Latics went close to a second goal, while at the other end Oxley made another smart save from Pigott's low drive.
Gillingham continued to pose a greater threat, with Weston and Adebayo Akinfenwa both failing to hit the target from good positions.
Oxley secured Oldham's win with two excellent late saves to thwart Akinfenwa and Cody McDonald.