Kazenga LuaLua’s cheeky backheel gave QPR the lead but Aiden McGeady cut in and curled an exquisite 20-yard equaliser on the stroke of half-time before Jordan Hugill notched the winner 20 minutes from time.
Freeman was then sent off for a second yellow card with 12 minutes remaining, with his second booking for a studs-up challenge on Tommy Spurr.
“I know Luke Freeman and I don’t think he put any weight on it,” said Holloway. “He’s tried to ride the tackle and not hurt anybody.
“Apparently the ref didn’t see it, the linesmen didn’t see it and the fourth official’s made an absolutely outrageous call and said it’s a second yellow.
“If it’s a stamping and it’s a deliberate stamping which he clearly says he saw, why isn’t that a direct red which we might be able to appeal?
“If someone stamps on you, I would definitely want them sent off – Luke didn’t do that. How can you make such a blatant error? I just don’t understand it.”
And Holloway believes the incident is the latest indication that replay technology is required in the Championship.
“Get the fourth official sat looking at a screen, for Christ’s sake, and get these decisions right,” fumed Holloway.
“If it’s good enough in the Premier League, then it’s surely good enough for this standard where we’re all trying to fight to get to the Premier League.”
Preston North End boss Simon Grayson praised McGeady’s ability to create something out of nothing.
“It was a disappointing goal to give away,” said Grayson of the QPR opener. “A long throw into the box, unfortunately it just went through Tommy Spurr’s legs and to be fair the lad (LuaLua) showed great awareness and good skill to put it in there.
“We ultimately responded well and when you’ve got somebody like McGeady who can do something out of nothing, it just shows the quality that the lad’s got.
“Hugill got into some good areas and unfortunately didn’t hit the back of the net but, for the winner, he reacted really well to lose his man and getting the first ball.
“He was first to react and the win gives us something to really build off.”
Grayson would have liked to see his team kill the game off once and for all after Freeman’s dismissal.
“Obviously the sending off happened and the game opened up,” he explained.
“Some of the play we had in that second half was exceptional but we lacked the ruthlessness to get the third and the fourth goal which would have made it a really comfortable afternoon.”