The Millers extended their unbeaten run to seven games after Ryan Williams’ early goal was cancelled out by Oldham’s Craig Davies.
It was far from a sparkling display by Warne’s men and the Latics were arguably the better team, but the Millers ground it out in a disappointing second half where neither side had a shot on target.
Former Oldham midfielder Warne said: “It wasn’t a game for the purists, the pitch was soft and wasn’t conducive to either team playing well. I thought in the first half we were in control of the game.
“The lads are disappointed in the dressing room because they feel like they have dropped two points, which is good from my point of view.
“We’ll pick up a point away from home, that’s seven unbeaten, we’re on a good little run. They are hugely motivated, which means it isn’t the worst day I have had.
“We just didn’t have enough quality today but I thought we defended resolutely at times.
“I was comfortable that we weren’t going to concede and on another day we could have nicked a win, but it wasn’t to be. We will take a point and we have two home games to look forward to.”
The Millers looked on course for another win when Williams slammed them ahead in the seventh minute but they could not build on that good start.
Davies’ 11th goal of the season on the half-hour drew Oldham level, it was a clever free-kick, and the home side had the better moments after that.
They got into some great positions but could not make their final pass count to leave boss Richie Wellens pulling his hair out as his side are now winless in seven.
“I don’t understand how people can get to the byline and not look up,” he said. “I think our final pass let us down today, we could have won the game.
“I cant think of another chance for Rotherham apart from their goal. It was an even game but we had the best chances to score.
“The amount of times when we broke in the second half but gave the ball away with our last.
“The players teased the supporters with little glimpses of what they are capable of without going full throttle – but there are good signs there.”
Pivotal game in Group E almost a pick ‘em with the bookies