Rangers assistant Gary McAllister says referee Don Robertson made the right call to keep Ricki Lamie on the pitch as he caught Joe Aribo with an elbow.
The Ibrox midfielder was forced off in the first half as blood gushed from his head after the coming together.
But McAllister insists Lamie made a genuine attempt to go for the ball in a summary at odds with Ibrox boss Steven Gerrard who insisted it was serious foul play.
McAllister also believes Filip Helander was lucky not to see red for his challenge on Lyndon Dykes.
He told BT Sport: "Well now that I've seen the Helander one, it looks like he's caught him so he possibly could go off.
"I think Lamie makes a genuine effort to go and head the ball, there's just that natural elevation with his arms. He's got his elbows up but I don't think there is a movement with his elbow to Joe Aribo. So good decision by the ref."
Rangers will now face Hearts in the Betfred Cup semi-final after a 1-0 win over the Lions.
McAllister reacted to the draw, saying: "We'll take that. The four teams that are left in the semis are all tough. We'll take that though."
It was a difficult night for Steven Gerrard 's men but McAllister says getting through to the next round was all that mattered.
He added: "I thought we dug in well. It was very difficult. Lyndon Dykes cause us problems the whole evening, it was very awkward to play against them.
"They've got a system and they stick by it and they're good at it. It wasn't easy, I don't think it was that pretty on the eye but we've ground out a result and we're happy."
