Josh Law’s late winner ensured 10-man Latics’ record of bowing out early in the League Cup continued for another year.
With extra-time looming and no winner in sight after an exchange of goals between Ryan Flynn and Will Grigg, defender Law struck home to give his side progression in this competition for the first time since 2008.
There were more half-chances than chances in the opening exchanges, as a Wigan side with six changes from the starting XI from Saturday’s defeat to Bristol searched for their rhythm.
Ryan Colclough found himself on the end of a couple of fouls as he led a series of reccies into Oldham territory early on.
Michael Jacobs’ free-kick in the seventh minute was Wigan’s first proper chance, though that failed to test Connor Ripley as it pinged off the wall for a corner.
And four minutes later there was a similar chance on the edge of the box as Colclough went down again - but this time Donervon Daniels’ header looked more of a threat to stewards in the back of the stand than the Oldham keeper.
The end-to-end nature of the game saw Colclough change roles as he conceded a free kick in a dangerous position, from which the best Marc Klock could do was win a corner - and form that the home side didn’t look like causing any damage.
That was until Flynn went on a run in the 19th minute, which at first looked unthreatening.
It was only by the time the ball had left his right foot, when he had made it half-way into Jussi Jaaskelainen’s box, that it even looked like going in the net - which it did after curling beautifully around the keeper’s outstretched arm at what seemed like a snail’s pace. It will divide opinion, probably depending on whose supporters you ask, whether it was a piece of individual brilliance or a soft goal.
Perhaps at this point the band of travelling supporters could have been forgiven for thinking they’d be left waiting for a first win at their first hurdle in this competition since beating Nottingham Forest in the second round of 2012.
But all the goal, and the home fans’ chanting of ‘Ryan Flynn’s on fire’, seemed to do was provide a kick in the backside to wake Gary Caldwell’s men up.
Powerful shots from Jordan Flores and Max Power stung the palms of those watching Ripley’s saves and a searching ball from David Perkins needed palming out for a corner to be diffused.
But as threatened, Wigan struck with a brilliant equaliser when Buxton’s cross was volleyed by Will Grigg - bringing out the most well-known version of the ‘on fire chant’.
It certainly made for better viewing than the schoolyard kick and chase of the opening exchanges, but there were also fireworks as Klok was shown a yellow card before Buxton’s straight red for a dangerous challenge well into added time.
As the floodlights became noticeable, reminding us light summer evenings are giving way to the cold and dark early-season ones, Oldham found some spark.
Flynn was first to test Jaaskelainen after the break and as the League One side applied more pressure, the home fans rediscovered the enthusiasm which got them out of the house for a League Cup round one game on a Tuesday night for.
Lee Erwin was next to have a realistic chance at putting his side in front with his 52nd-minute header, which received a more dramatic gasp from the stand than it probably deserved.
While it was close to the line, it was never in danger of crossing it into the net given Jaaskelainen’s cover.
Wigan were left holding on to the point where you could be forgiven for being sure a goal to nudge the home side ahead was coming, and when skipper Peter Clarke sent a bullet header Jaakelainen’s way, their fans were convinced too.
It wasn’t quite flinging pies in the air territory, but it took a while for their cheers to die down once the clatter of the advertising hoarding signalled the ball was wide.
But despite being down to 10 men, this wasn’t yet a question of how long Wigan could hold out for.
Colclough was still looking for work, creating Wigan’s best chance of the half for Jacobs, which was met by hands over faces in the away end - and as Flynn’s next test of Jaaskelainen was easily met, fans were beginning to text partners to tell them not to wait up as extra-time loomed heavily on the horizon.
But the extra-time never came, as Oldham had one last push in them as time ticked into the 83rd minute when Law slotted the ball in, to the roar of of Oldham’s fans.
While their chants of ‘Wembley, Wembley’ may have been in half-jest while they waited a nervy four added minutes for the referee’s whistle,at least they went home happy.