A dreadful decision by assistant referee Graham Chambers robbed Dundee United of a penalty and got striker Simon Murray sent off at Tannadice.
Murray had been booked for simulation in the first half when challenged by Hamilton skipper Massimo Donati.
He was then wrongly red-carded by referee Steven McLean for “diving” once again when he was kicked in the knee by Accies player Scott McMann on 77 minutes and went down in the box.
McLean appeared poised to point at the spot at first but Chambers’ flag changed his mind and Murray was sent packing.
Not only were the Tangerines a man down through no fault of their own but they missed out on a golden opportunity to take a lead down the road to New Douglas Park on Sunday in this two-legged Premiership play-off final.
The club can lodge an appeal through the fast-track system and the ban would be frozen until the hearing.
As it is was the match finished goalless and the teams will have to do it all again in the return match.
The game was also marred by a show of petulance from United midfielder Wato Kuate, who reacted badly to being substituted on 56 minutes and stormed off up the tunnel.
The Tangerines had named an unchanged starting line-up from the side that started the game semi-final at Falkirk on Friday night.
There were a couple of new faces on the bench, though, with Ali Coote and Lewis Toshney replacing Scott Fraser and Scott Allardice.
The big miss for Hamilton was their injured skipper Mikey Devlin, with Donati coming into the centre of defence instead.
There was an impressive flag display from the fans in the Eddie Thompson Stand before an impeccably-observed minute’s silence was held in remembrance of those murdered in the Manchester terrorist atrocity.
Accies, playing in blue strips, got the action under way but United quickly got a hold of the ball and a Paul Dixon cross had to be cleared by the away defence.
Good play by Blair Spittal on the right on five minutes saw the midfielder play in Murray but the striker had strayed offside.
Kuate, who had endured a dodgy start to the match, was giving the ball away too often but he wasn’t the only one.
On one such occasion, United were almost punished when Rakish Bingham raced up the right, with keeper Cammy Bell having to dive to smother his cross.
Kuate was at it again on 12 minutes, with his dithering on the ball leading to another break from the visitors, this time Bell doing even better than before to come out and save Bingham’s shot.
It was game over for one spectator when it was announced over the Tannoy that his wife had just gone into labour!
Murray hit back for the hosts a couple of minutes later when he cut in from the left before unleashing a low shot with his right foot that was saved by Hamilton goalie Remi Matthews.
Some dreadful defending by Accies on 17 minutes almost left the way clear for first Thomas Mikkelsen then Andreu but Matthews raced out of his goal to boot the ball out of play.
The Dane and Frenchman then almost go on the end of a ball from Dixon after United had broken well up the left again.
Dixon was causing the visitors problems and he whipped in another cross on 27 minutes that was knocked down by Mikkelsen for Murray but he couldn’t get his strike away.
There was a moment of controversy on 31 minutes when Murray raced into the Hamilton box before hitting the deck after being challenged by Donati.
The supporters behind the goal wanted a penalty but McLean instead booked the United frontman for simulation.
Ali Crawford shot wide for the visitors on 37 minutes before the first half fizzled out and it was on to the second period, with United shooting towards the Shed.
Mikkelsen was unlucky on 51 minutes when he chased down a passback only to have the clearance smashed against him by Matthews. Remarkably, he was penalised for handball.
Just a minute later, Murray ran clear as United had a three on two but he tried a shot instead of passing and it was deflected for a corner.
David Templeton, who had a spell training with United earlier in the season, threatened for Accies on 54 minutes as his low shot was deflected just wide of the far post.
On 56 minutes, Kuate came off for Charlie Telfer and the Portuguese player wasn’t happy, brushing away teammates Dillon and Durnan before running up the tunnel.
It was a regrettable reaction by a player who had been having a poor game.
Telfer was involved straight away, with his corner headed goalwards by Mikkelsen and almost sneaking in at the keeper’s top corner.
Imrie was yellow-carded for a bad tackle on Mikkelsen then Durnan almost grabbed the lead when he blasted over the bar from 18 yards when upfield for a corner. Imrie then had a chance at the other end but poked his shot wide.
Durnan then rose to get his head on a Dixon freekick and, as Matthews stretched to save, ref McLean blew his whistle for a push.
Crawford had a great chance for Accies on 75 minutes when he was found in space inside the box by he skewed his shot wide again.
Just a couple of minutes later, United were up against it when they lost Murray to another booking for simulation.
This time there was no doubt about it – he was fouled and it should have been a spotkick to the Tangerines.
He was kicked in the knee by McMann and it it should have been advantage United rather than a man down.
Neither side could find the net in the time remaining and the United players will go west feeling they were hard done by.
Dundee United: Bell, Dillon, Dixon, Durnan, Spittal, Murray, Edjenguele, Flood, Kuate (Telfer 56), Mikkelsen, Andreu (Nicholls 87). Subs not used: Zwick, Donaldson, Toshney, Coote, Robson.
Hamilton Accies: Matthews, Skondras, Imrie, Redmond (Docherty 74), Crawford, Gogic, Bingham, MacKinnon, Donati, McMann, Templeton (Longridge 63). Subs not used: Woods, Gillespie, D’Acol, Watson, Want.
Referee: Steven McLean.