Dundee United missed out on a trip to Hampden Park after going down 2-1 to Morton in the Betfred Cup quarter-final.
Ton attacker Jai Quitongo blasted the home side into the lead in the 24th minute before stand-in skipper Thomas O’Ware added a second just after the half-hour mark with a header.
Nick van der Velden reduced the deficit in the 55th minute with a drive but Jim Duffy’s side held out for a landmark quarter-final victory.
The result came as a bitter disappointment for Arabs and Ray McKinnon feels their pain.
The dejected gaffer let his players know that a similar performance “will not be tolerated again”.
He said: “That is not good enough for me and they are aware of that now.
“I am pretty disappointed with them tonight and I told them that.
“In the first half we wanted to pay tippy-tappy football with no purpose. We never threatened them enough for me, we had a lot of possession but did nothing with it.
“We got caught with set piece and an horrific first goal, so avoidable.
“So it is very frustrating and I am very disappointed with them.
“We worked on crosses but I think it is desire. They wanted to head that ball more than we wanted to head it, that is frustrating that we are not matching that.
“I am not going to give them any credit for the second half because effectively I don’t think they were any better than the first half.
“We were ragged, there was no penetration. We got the goal back and for the spell it looked like we would get the equaliser but we are better than that.”