Dundee assistant supervisor Simon Rusk felt let down by the officers after they awarded James Tavernier a penalty in his facet's 3-0 dwelling Scottish Cup defeat to Rangers.
The guests had been a aim up when Tavernier was bundled over by Ryan Sweeney contained in the field halfway by the primary half.
And match official Steven McLean confirmed no hesitation in pointing to the spot.
Rusk informed Premier Sports activities: "Clearly we're disenchanted with the choice for the penalty.
"I've not truly seen it again but. I have been informed it is delicate.
"Rangers had been all the time going to trigger us issues. We maybe did not take care of these issues they had been providing effectively sufficient early within the recreation."
Rusk, who was deputising within the absence of supervisor Mark McGhee, is aware of the cup exit is not season defining because the Darkish Blues combat on the foot of the desk domestically.
However he believes enhancements are wanted for a similar fixture in opposition to the title hopefuls within the league subsequent Sunday.
"The result's the consequence. Clearly disappointing as a result of it is the cup," added Rusk.
"The early aim causes us plenty of issues after which from there it is preserving your form and looking for that steadiness of simply staying within the recreation however not taking to a lot of the sport that you're out of it.
"We've got to be mentally powerful. We've got to take a look at the sport. What may be higher and take it into subsequent week's fixture in opposition to the identical opponents."