Jack Ross refused to use Kevin Clancy's failure to dismiss Alfredo Morelos for an apparent stamp on Ryan Porteous as an excuse for Hibernian's defeat to Rangers, but insisted the official had made an error in missing an "easy" decision.
The Colombian forward appeared to drive his studs into the Hibs defender's thigh in the latest clash between the two players following several incidents in previous games between the sides.
Morelos escaped reprimand from the referee and compounded the hosts anger when he netted the only goal of the game in the second half to extend Rangers' unbeaten run to 26 Premiership games.
But while Ross could not justify his side switching off to hand the striker his opportunity, the Easter Road boss made no secret of his disappointment towards Morelos remaining on the pitch long enough to score.
"It's a red card," he said after the final whistle.
"You can ask me and I don't think my opinion is going to be any different from anyone here or anyone who watched it, it's quite an easy one but obviously it's been missed by the match official.
"I wouldn't use it as an excuse for how we conceded the goal because that was one lapse from us.
"We should have defended the goal better irrespective of the player who scores the goal, i'm not going to point to that as an excuse for conceding the goal.
"But I would point to the fact that he shouldn't have been on the pitch."
Hibs performed better than their meek surrender of the Betfred Cup semi-final defeat to St Johnstone on Saturday, but Ross could only watch as his side spurned chances to take something from the game.
Jackson Irvine and Christian Doidge were the most guilty parties, both missing first half opportunities as Hibs failed to end a two-year run of failing to win back-to-back home games.
Ross was encouraged by the performance despite the result and challenged his players to produce it on a more regular basis.
“I was critical of them publicly and I was critical of them privately and they answered every one of them tonight bar the result," he said.
"But that type of performance will stand us in good stead for the rest of the season.
“We’ve put ourselves in a good position but we need to get back to winning games regularly. We’ve had a strange fixture list where we’ve played Ranges twice and Celtic away in the last six games so we've got a period coming up where we believe if we produce that type of performance, we can get back to scoring goals regularly and winning games."
