The Kilmarnock manager displayed his fury that the official had ignored what he believed was a penalty in the final seconds when Inverness Caledonian Thistle's David Raven downed Rory McKenzie in the area seconds after Borja Perez snatched a equaliser. But if Shiels was angry, Terry Butcher was incandescent that his side squandered two points in the final moments as Perez finished off a dazzling run by James Dayton.
"I am bitterly disappointed," he said. "On scale of one to 10, I would say 50, if not 100. We dominated and if it was a boxing match Kilmarnock would have been counted out.
"The longer the game goes on at 1-0 the more that they have a slim hope. Even then I still expected my back four to hold out and not dive in which they did. I think it was the only shot Kilmarnock had and we had countless chances to have won it.
"I just can't believe it, seven times we have been in winning positions and have conceded a late goal – 14 points we have thrown away. If you look at it, 14 points would have got us second spot. We only have ourselves to blame, no one else for not doing our jobs."
Shiels made light of his sending off and suggested it was a formality after he had inadvertently kicked a water bottle. "What happened was I was frustrated he didn't give the penalty" he said. "I turned around and kicked fresh air and there was a bottle there. I said 'look, I didn't mean to kick the bottle'. But the rules have been changed because Neil Lennon and Steve Lomas had theirs rescinded.
"Neil Lennon kicked the bottle up at this ground but didn't get anything against him. But then I'm not Neil Lennon. It's okay. Nothing will be done. The fourth official said it was just protocol, that 'we have to do this because there's somebody watching me in the stand.' He said don't worry about it, there will be nothing done. It's a ridiculous ruling. We both agreed that."
If there were suspicions that Inverness' bubble had burst following a run of poor results, someone forgot to tell the players. The outcome may have been tight, but the performance was as clear an indication as possible that the Highlanders' surge to second place in the Clydesdale Bank Premier League is merited.
Kilmarnock found it hard to find fluency and frequently appeared uncomfortable, giving the ball away too easily and failing to make an impact in the final third, although a Paul Heffernan strike across goal wasn't too far away.
It was Nick Ross who broke the deadlock with a fine goal for the hosts after 21 minutes, stabbing home Aaron Doran's low cross after the winger had mesmerised the Rugby Park defence to create space.
In truth, the opening 45 minutes were comparatively easy for Inverness, who might have gone it at the break three ahead. That troubled Shiels, as did the embryonic phase of the second period as his men allowed Inverness to continue their domination.
Gary Warren and Graeme Shinnie both went close with fine efforts but it was Perez's late strike that brought gasps from the home crowd as Butcher reacted badly to their jeers at the end.
"We are only one point ahead of Motherwell with eight games to go," he said, "We feel that we should be three, definitely. I honestly don't know how much more we can do when you look at the crowd."