Hamilton Accies slipped to their seventh successive defeat in the Scottish Championship - as one of their former players heaped more misery on John Rankin's rock-bottom side.
Josh Mullin, who spent last season on loan at Hamilton from Livingston, netted a deflected free-kick after 31 minutes to claim all three points for Ayr United, and keep Accies six points adrift of nearest rivals Arbroath at the foot of the table.
Accies were boosted by the signing of two new defenders on loan just before kick-off, with Tom Sparrow coming in from Stoke City and Dylan McGowan arriving from Kilmarnock, but they were unable to keep the title-chasing Honest Men at bay.
While shoring up the defence will be welcome, that's now five games without a goal for Accies and Rankin will surely be pursuing more firepower in the January window after another dismal showing in front of goal mustered just one shot on target.
Accies made three changes from Monday's 1-0 defeat at home to Raith Rovers. The two new signings came in alongside Andy Winter, as Fergus Owens, Dario Zanatta and the injured Andy Ryan dropped out.
Rankin had mentioned during the week that illness was disrupting their preparation and 16-year-old regular Ryan One wasn't well enough to be included in the squad.
The sides battled out a 2-2 draw in August and Ayr triumphed 3-2 away from home in November, so it was no surprise to see another tight affair.
It was the hosts who threatened first as Logan Chalmers burst down the right-hand side, into the box and fired a low strike at goal, but Ryan Fulton was equal to it in the opening 70 seconds.
Andy Murdoch's game lasted less than three minutes as he hobbled off holding his thigh and Paul Smith was introduced to the action for Ayr.
Accies had a half-hearted penalty appeal turned away in six minutes when Winter muscled his way into the box and went down under pressure.
And Ayr should have opened the scoring after 13 minutes when they caught Accies out with a quick free-kick just outside the box. Dipo Akinyemi's delivery across the face of goal fell kindly from Michael Hewitt and, thankfully for Accies, he blazed his effort over the bar.
Moments later, a chance fell the way of debutant McGowan, who was skippering the side, when Reegan Mimnaugh's free-kick picked him out in the box, but he headed wide of the target.
Ex-Accie Josh Mullin was denied the opener for Ayr in 19 minutes when his goal-bound strike was kept out by Dan O'Reilly with Fulton beaten.
Skipper Sean McGinty had an acrobatic effort kept out as the Honest Men pushed for the opener.
And it eventually arrived in 32 minutes. Akinyemi cut across the edge of the box and Scott Martin hauled him down with a poorly-timed challenge, which earned him a booking. Mullin stepped up and when his low free-kick took a defelection off the wall, the ball skidded past Fulton and into the bottom corner.
It had been coming but Accies almost equalised just before the break when a cross broke to Lewis Smith inside the box, only for his fierce strike to be blocked.
In first-half stoppage time Mimnaugh looked to have levelled when O'Reilly headed the ball across the face of goal. Somehow, the ball was cleared off the line by Hewitt and over the crossbar as Mimnaugh tried to nudge the ball into the net.
Early in the second half Michael Doyle got caught in possession and Ayr were two-on-two but the Accies defenders tracked back well to do enought to put off Ben Dempsey as he tried to curl one into the far corner.
It wasn't long before Doyle was replaced by young Fergus Owens and Lewis Smith was also sacrificed to make way for Frenchman John-Pierre Tiehi, to try and add some physicality to the frontline.
While Accies made a decent fist of it, opportunities were hard to come by as Ayr looked content the would be able to hold on to their advantage and they saw the game out with reasonable ease, as a Tiehi clearance off the line in stoppage time stopped Ayr adding to the scoreline.
Accies are back in action on Tuesday night when they host Clyde in the SPFL Trust Trophy quarter-finals.
AYR: Albinson, Kirk, McGinty, McAllister, Reading, Murdoch (Smith 3), Mullin, Chalmers (Mitchell-Lawson 83), Dempsey, Hewitt (McKenzie 70), Akinyemi (Bryden 83).
Scorers: Mullin 32
Bookings:
Subs not used: McAdams, Bilham, Ecrepont, Tomlinson, Ashford.
HAMILTON: Fulton, Doyle (Owens 57), McGowan, O'Reilly, Shiels, Sparrow, De Bolle, Martin (Zanatta 77), Mimnaugh, L Smith (Tiehi 57), Winter (Forsyth 85).
Scorers:
Bookings: Doyle, Martin
Subs not used: J Smith, Easton, McGinn, Latona, Morgan.
Ref: Calum Scott
HT: 1-0
Att: 1,988
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