The Shrimps suffered their first home league defeat under Derek Adams as Oldham Athletic take all three points at the Globe Arena.
Oldham took a first half lead when Segbe Azankpo made the most of a Mark Halstead error. The Shrimps found themselves level when Carlos Mendes Gomes converted his chance early in the second half but were beaten by a scrappy goal from Mohamed Sylla.
Morecambe boss Adams started with the side that started the second half against Newport in Saturday’s excellent comeback win with starts for Kevin Ellison and Cole Stockton and the Shrimps put early pressure on Dino Maamria’s side.
It was Oldham who had the first effort of note when Jonny Smith forced Mark Halstead Into a decent save low to his left after some good interplay around the Shrimps’ box.
On the 20th minute mark, Mendes-Gomes kept his composure to twist and turn on the edge of the penalty area before leaning back and sending his effort over the bar into the home stand.
A few moments later the Shrimps went a bit closer when Luke Conlan tried his luck from 30 yards with a free-kick that crashed against the crossbar.
Despite the early pressure, the Shrimps found themselves a goal down on the half-hour when Azankpo bundled the ball over the line after Filipe Morais’ effort from range was spilled by Halstead.
Both sides continued to threaten and he Shrimps went close on the stroke of half time when Stockton’s cross looked set to be met by Ellison at the far post but former Shrimps’ favourite Zak Mills reacted sharply to turn the ball away to safety.
The Shrimps’ pressure continued after the break and they levelled two minutes after the restart when A-Jay Leitch-Smith produced a moment of brilliance to take control of a long ball and tee up Mendes-Gomes who slotted the ball underneath visiting keeper Zeus De la Paz.
The game then swung from end to end.
On 50 minutes Azankpo worked an opening in the box but on this occasion saw his effort from the angle well saved by Halstead.
The Shrimps responded with Stockton wasting a glorious opportunity to put his side ahead when he was gifted a free run on goal by David Wheater but blazed over from close range when he should have scored.
He was almost paid to pay immediately as Oldham substitute Scott Wilson created an opening for himself but drilled his shot against the foot of the post from the edge of the box.
It was the visitors who did score the next goal however with midfielder Mohamad Sylla tapping in from close range after a number of shots were blocked by Morecambe on the 75th minute.
Alex Kenyon did get the ball in the net for the Shrimps only to see his effort ruled out for offside as the Shrimps went down to a second defeat this season against Oldham.
Morecambe: Halstead, Conlan, Kenyon, Old, O'Sullivan, Stockton, Leitch-Smith, Ellison, Brewitt (rep Sutton 85), Mendes-Gomes (rep Miller 79) Tanner.
Oldham Athletic: De la Paz, Mills, Iacovitti, Morais (rep Wilson 68), Maouche (rep Eagles 80), Azankpo (rep Egert 87), Sylla, McCann, Smith, Wheater, Hamer.
Referee: Anthony Backhouse