Alfredo Morelos should have been sent off before scoring the winning goal for Rangers at Easter Road, says Hibernian head coach Jack Ross.
The Colombian striker knocked in his 11th goal of the season to keep the Ibrox side 23 points clear at the top of the Scottish Premiership.
But Ross thinks he should have been dismissed for an apparent first-half stamp on Ryan Porteous.
"It's a red card; it's quite an easy one," Ross told BBC Scotland.
"We get the benefit of seeing it again but it's one that looks relatively straightforward in real time as well. It should have been seen and I'll just keep it at that.
"I don't want to use that as an excuse for the goal because, in that moment, we should have defended it better."
Morelos went on to knock in the game's only goal, finishing off a slick move on 51 minutes as Rangers made a strong start to the second half.
The Ibrox side are now within eight wins of their first top-flight title in a decade and manager Steven Gerrard preferred to focus on the performance of his team rather than the Morelos controversy.
"I haven't had time to look at any of the incidents from the game," he said. "I remember a few from both sides.
"It was another fantastic team goal. Alfredo will deserve the credit for finishing it off. I took him off at the weekend to have him really fresh for tonight because I knew he'd have to do a lot of running.
"I think we deserved that team goal because of the application we've given to the game.
"This was a tough fixture. People on the outside would have looked at it as one were we could have a bit of a bump but our performance deserved what we're taking away from here tonight."