9 man Morton dug out a dramatic win on penalties as this Belief Trophy conflict descended into chaos late on at Cappielow.
Ref Craig Napier flashed three reds as either side have been left infuriated on the whistler's efficiency.
However it was Ton who stored their cool to return by means of on penalties with solely Ayr skipper Sean McGinty lacking from the spot.
Lee Bullen had rung the adjustments with seven contemporary faces into the beginning line up, together with a primary begin for David Bangala in a 4-3-3.
Josh Mullin and Brad Younger additionally made their first begins since signing on mortgage earlier this month.
However United endured an unsure begin and have been behind with the sport simply 12 minutes outdated.
The guests could not clear their traces from a Morton free kick and when the ball fell to Lewis McGregor, his shot was deflected off Nick McAllister and previous the helpless Aidan McAdams.
Ton got here near doubling their lead halfway by means of the half however Alan Lithgow despatched an overhead kick straight at McAdams from 12 yards.
On the different finish, Sam Ashford had Ayr's first sight of purpose with a driving run and shot which was straight at Brian Schwake.
However United have been warming to their job and bought the leveller simply earlier than the break when the spectacular Younger pulled again for Mullin to transform with a primary time effort into the underside nook.
Ton started the second half brightly and former United man Jack Baird compelled an excellent save from McAdams with a header from a nook.
Jai Quitongo then fired inches previous following one other set piece, earlier than Baird scooped over from beneath the bar as Morton pressed laborious.
Then got here the large flashpoints as either side have been diminished to 10 males - choices that sparked anger from all sides.
Paul Smith was first to stroll for Ayr after a problem on Lewis Strapp drew what seemed to be a harsh second reserving.
And simply moments later, ref Craig Napier evened the chances with a straight purple for Quitongo following a conflict with Paddy Studying on the touchline.
Bullen turned to his bench, sending on Dipo Akinyemi, Mark McKenzie, Andy Murdoch and Mikey Hewitt as Ayr appeared for contemporary legs to win it.
And Akinyemi nearly teed up McKenzie with an excellent piece of play which noticed the latter sting the palms of Schwake.
Then got here extra card drama as Baird was the following man to see purple for Morton after hauling down Murdoch on the sting of the field with the Ayr man trying to house in on purpose.
However Ton managed to barter the ultimate moments with simply 9 males earlier than coming by means of on penalties.
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