Two of the second division's big promotion rivals fought out an entertaining clash that was dramatically settled by a late Crewe double.
Oldham looked on course to take a point despite having Fitz Hall sent off in the first half but arch-marksman Robert Hulse took his season's tally to 22 and substitute Dean Ashton finished them off.
Oldham have suffered three red cards in three games and manager Iain Dowie was furious with the referee after Hall walked for a professional foul which stopped Steve Jones going clear.
Dowie stormed: "It was not even a booking, never mind a sending off, and yet again the officials got it completely wrong.
"Fitz is a cultured centre back and one of the best young talents in the country, but he has a bad record and that shows what we are up against.
"We have got problems if football is becoming a non-contact sport but I am proud of my players. We played very well and the better side lost." Crewe replaced Oldham in the top two and boss Dario Gradi was delighted with his team.
"Their man was sent off quite early but I was still concerned because Oldham are such a big side," he said.
"I told my players to keep playing football because we could dictate the game by passing it around. They were men instead of boys and passed the test very well." But Gradi faces a goalkeeper crisis as his two main stoppers are injured and on loan Danny Milosevic was carried off on his debut with a neck injury.
Gradi turned to teenager Stuart Tomlinson for the last 40 minutes but he is likely to check his options.
Oldham dominated early on but Hall was sent off just before the half-hour and Crewe took over.
They went in front when Hulse arrived at the near post for an excellent finish eight yards out only for Oldham's Chris Armstrong to level with a low shot into the corner from 12 yards after Ben Burgess' pass.
Both sides attacked in numbers but it was Crewe who struck in the 86th minute when Lee Duxbury's goal-line clearance fell to Hulse who smashed hi shot home from 12 yards.
Substitute Ashton soon added a third when his drive from the edge of the box bobbled out of the keeper's grasp.