Ayr goalkeeper Graeme Smith saved two penalties but could not prevent his side from losing 1-0 to play-off hopefuls Arbroath.
The visitors made a strong start to the match and should have taken the lead in the 17th minute when they were awarded a penalty for Neil McGregor's foul on Graham Bayne but Smith produced a wonderful save to deny Steven Doris from the spot.
Arbroath were awarded a second penalty in the 56th minute when Jackson Longridge handled in the area but Paul Sheerin's penalty was well saved by Smith.
The Smokies finally took the lead in the 60th minute when Euan Smith got on the end of Daniel Rennie's cross to head home from close range.
Ayr pushed for an equaliser in the closing stages but Arbroath held on to take all three points.