Latics were left heartbroken as two late goals for Doncaster Rovers meant the game ended in a draw.
Jabo Ibehre had given Latics the lead going into the break and ten minutes into the second half, George Elokobi extended their advantage.
Controversy followed with 15 minutes remaining as Joseph Mills received a straight red card for a foul on Reece Wabara.
Ten minutes from time, substitute Nathan Tyson pulled a goal back and deep into stoppage time, James Coppinger curled a shot past Rachubka as both sides settled for a point.
The game started very evenly with both sides enjoying good spells of possession without creating a real clear cut chance.
Jonathan Forte was the first to go close after meeting a Joseph Mills corner into the box but his header just went over the crossbar.
Only a minute later, Paul Rachubka's mistake allowed Theo Robinson a chance to score but the Doncaster striker stuck it over the bar to save the blushers of the goalkeeper.
Rovers started to gain slight control on the game and Harry Forrester should have done better from ten yards when presented with the chance.
On 15 minutes, Forrester again was allowed space to shoot from distance but his effort crashed off the crossbar and away from danger.
Latics responded well with Carl Winchester, Liam Kelly and Danny Philliskirk putting pressure on the Rovers defence and causing problems.
Doncaster defender Andy Butler was pressured into a mistake by Forte and he fed Ibehre inside the box to fire past Sam Johnstone to give Latics the lead on 23 minutes.
As the hailstone started to fall over SportsDirect.com Park, Athletic started to dominate the game.
Winchester fired wide under no pressure just after the half hour mark and Brian Wilson came inches from grabbing his first for the club as his 30 yard effort flew the wrong side of the post.
The second half started much the same as the first with both sides enjoying spells of possession.
Latics did extend their lead ten minute into the half through Elokobi. The central defender bulldozed his way above everybody in the box and the linesman adjudged the ball to have crossed the line to the delight of the home supporters.
Just after the hour mark, Ibehre thought he had made it three but his shot was deflected over the bar by a Doncaster defender on the line.
Winchester was the next man to go closest as he received the ball from Ibehre inside the box but he just scuffed his shot past the post.
With only 15 minutes of the game remaining, the controversy started. Mills was given a straight red card for what the referee perceived to be a lung on a Rovers player and he departed.
The referee made himself further unpopular with the home support as Doncaster pulled a goal back.
Paul Rachubka appeared to be fouled as he went up for the ball with Tyson and he bundled the ball into the back of the net to give the visitors a lifeline in the game.
The visitors were in the ascendancy and Latics bought David Mellor and Amari Morgan-Smith into the action to stem the pressure of attacks.
The defence held strong until the last minute of additional time as Doncaster found a leveller.
Coppinger cut inside the defence and curled an effort low past Rachubka to level the game and the points were shared.
Oldham Athletic: Rachubka, B.Wilson, J.Wilson, Elokobi, Mills, Kelly, Jones, Winchester (Mellor 79'), Philliskirk, Forte (Morgan-Smith 82'), Ibehre.
Subs not used: Brown, Dieng, Dayton, Poleon, Coleman.
Doncaster Rovers: Johnstone, Robinson (Main 60'), Forrester, McCullough, Butler, Stevens, Keegan, Wellens, Wabara, Bennett (Tyson 60'), Coppinger.
Subs not used: Marosi, McCombe, Wakefield, De Val, Middleton.
Goals: Oldham Athletic (Ibehre 23', Elokobi 54') 2-2 Doncaster Rovers (Tyson 79', Coppinger 90+5')
Attendance: 4,181 (610 visiting supporters)