Shawn McCoulsky boosted Maidenhead's National League survival hopes with the only goal in a win at promotion-chasing Oldham.
In a first half most notable for Latics' boss Micky Mellon's dismissal following a difference of opinion with Maidenhead defender Miles Welch-Hayes, it was the hosts who made the better of the chances.
Joe Pritchard, Mark Kitching and Tom Pett all went close to opening the scoring, but it remained all square at the break.
The deadlock was broken with 64 minutes gone when McCoulsky fired the visitors, who had started the evening in 20th place, into a priceless lead, accepting Tristan Abrahams' lofted pass before beating keeper Tom Donaghy.
Substitute James Norwood twice went close to an equaliser as the hosts threw everything they had Maidenhead, but they held firm to climb four points clear of the relegation zone.
Report supplied by PA Media.
