QPR manager Mark Warburton was incensed by referee Keith Stroud's decision to award the free-kick which led to the goal.
After Sam Field was adjudged to have fouled Jefferson Lerma, the ball was swung in from the left by Junior Stanislas and Dominic Solanke flicked a header into the far corner of the net.
Rangers ended the match with 10 men after Andre Dozzell was sent off in stoppage time and they failed to find an equaliser which saw them lose 1-0 to Bournemouth who moved top of the Championship.
After Solanke had tangled with Yoann Barbet, players from both sides became involved in a melee and Dozzell's involvement led to him being given a second yellow card.
"I've just got to question the obvious decision-making process," Warburton said.
"I've got to be very careful what I say, but I'm just bemused by decisions. I'm amazed.
"There are fine margins in the Championship and that was the defining moment in the game.
"Should we have defended it better? Absolutely. We should have had first contact on the header. Was it a free-kick? How? I've just seen it again. How?
"Sam goes down and somehow he gives a free-kick and it's a yellow card. I'm just totally bemused by it. Please explain.
"I saw decisions all afternoon. I appreciate the difficulty of the game. I appreciate how instantaneous their decision-making has to be, but I've got to question many things.
"We end up with young Andre Dozzell getting sent off which, again, I'm bemused about.
"I've got to see it again to try and understand it. He's raging in the dressing room."
Bournemouth boss Scott Parker was full of praise for striker Dominic Solanke who notched the winner.
"The boy's got laser focus about him. He's a driven boy.
"He misses the chance and at that moment there's two ways to go - and he then executes a great finish.
"I'm his biggest, biggest supporter. What that boy gives to this team in terms of his goals, general play and work-ethic is incredible."
QPR will now travel away to Bristol City this evening (Thursday) as they bid to bounce back to winning ways in the Championship.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here