Reds boss Danny Wilson praised his side following a fourth straight home win in the league.
A first-half strike from Kane Hemmings secured the points against Play-Off chasing Oldham.
Speaking to Barnsley Player, Wilson said, "We deserved it because we've taken a great chance in the first 10 minutes or so and defended fantastically after that.
"If you look at the saves that Ross has had to make, it's been few and far between. Although they've had possession in key areas, we've frustrated them and the way they wanted to play.
"I thought the team ethic and the team work was absolutely outstanding."
The team performance of graft and determination was epitomised by full-home-debutant Josh Scowen, who scooped the sponsor's man of the match award.
"He's a little pocket dynamo, isn't he?" continued Wilson.
"He's unassuming and gets about his business, he's very quiet but very effective. I thought he was outstanding. Him and (Ben) Pearson in those two central roles were outstanding.
"I thought the work they all did - with Conor on the outside - did negate a lot of their forward play.
"That made it a bit easier for the back four but I thought the back five were outstanding again. They've snuffed out nearly everything they and we've had our chances."