United were up against both a determined Ayr United starting eleven as well as the horrendous weather conditions with gales hindering any chances of silky football being played. United fell behind in 12 minutes when former Tannadice player Scott Crabbe put the Somerset Park side ahead from the penalty spot. United struggled to create any meaningful chances during the first half with the exception of Lilley hitting the woodwork on the half-hour mark. Ayr were deservedly in the lead as the referee blew for half time.
In the second half, the Tangerines failed to exploit the blistering conditions, now having the wind in their back and it was Ayr who scored again increasing their lead in the 79th minute when Paul Sheerin blasted the ball past Gallacher with a low drive from outside the box.
It was a disappointing performance from Alex Smith's side as First Division Ayr claimed their fourth SPL scalp of the season.
Dundee United: Gallacher, Hannah, Lauchlan, Easton, Miller, Lilley, McCunnie, Griffin, Venetis, Thompson, McCracken.
Subs: Jarvie, Winters, Carson, McConalogue, Aljofree.