"There were many aspects of our play that weren't as we want them. We ground out a result and you have to do that sometimes," said Rovers boss Paul Trollope.
"We've created an expectation of flowing football among our supporters and sometimes the opposition stop you playing that way.
"Oldham did that very well by closing us down at every opportunity, but I thought they might struggle to do that for the entire 90 minutes and it proved that way. We kept going until the final whistle and got our reward."
Oldham boss Dave Penney: "It was certainly a performance for us to build on. It was a good team performance. We got the ball down and passed it and looked a decent side.
"But we didn't see the game out and that's something we have to work on. Rovers took their chance and we didn't.
"Away from home you have to take the opportunities that come your way. This was always going to be a tough match for us and there were a lot of positives to take out of it.
"You could see how disappointed our players were at the final whistle. It's always cruel to concede so late because there is not time to do anything about it."