Rovers, in need of victory to climb above Dundalk and St Patrick’s Athletic, were labouring against opposition who went into the game having taken a single point from their previous 11 league games when Zayed was introduced as a 62nd minute substitute.
He made a quick impact, scoring a stunning volley from a fine Ronan Finn pass within four minutes of his introduction.
Ciaran Kilduff should have made the game safe on 81 minutes but, having taken the ball round keeper Paul Skinner, his weak shot was cleared off the line by retreating right-back Stephen Quigley.
The miss almost proved costly as Athlone almost snatched an unlikely point in stoppage time when a free-kick from substitute Ian Sweeney forced Rovers keeper Barry Murphy into a decent save.
Elsewhere on Saturday, Sligo Rovers continued their recent resurgence with a 3-0 win Bray Wanderers at the Showgrounds.
Paul O’Conor put Sligo in front after 19 minutes as he got on the end of a Danny North knockdown before sliding the ball to the net.
Sligo doubled their advantage 10 minutes into the second half courtesy of a cracking volley from John Russell.
When the third eventually came it was two substitutes that combined to create it. Sean Maguire took on the Bray defence, before threading a ball across the area for Eric Odhiambo to rifle a shot high into the net from close range.
Victory brought Sligo’s points haul from the last five league games to 13 from 15 and saw them climb above Saturday’s opponents into fifth, nine points behind Shamrock Rovers but with a game in hand.
In the First Division, Cobh Ramblers remain winless after succumbing to a 2-0 defeat by Longford Town at the City Calling Stadium.
David O’Sullivan scored both goals — his fifth and sixth of the season — to lift Longford Town from seventh to fourth.
Ramblers remain rooted to the foot of the table.