Hearts vs Celtic ref watch as controversial moments analysed
Jorge Grant and Lawrence Shankland scored in either half as 10-man Celtic were put to the sword at Tynecastle.
The game was action-packed from start to finish, with no shortage of talking points.
Here's how we saw the major calls that were made in the match...
Celtic penalty
Alex Cochrane was punished for a collision with Yang inside the area during the opening moments of the match.
The referee pointed to the spot in what on the face of it appeared to be a straight-forward decision.
However, when looking at the replays, both players looked to be culpable in what was ultimately just a tangle of legs, with neither player at fault.
That said, the Celtic player was impeded as he entered the box, and so the officials did what they deemed to be right. Zander Clark would save from the in-form Adam Idah regardless.
Verdict: Correct decision
Yang red card
This one could be debated until the cows come home, ultimately.
The long and short though, is that the South Korean's boot was high and caught Cochrane in the head as he challenged for the ball.
READ MORE: Hart says 's****bag' as Shankland avoids Hearts vs Celtic pen
There was undoubtedly no intent, but the endangering of an opponent does not legislate for that.
VAR was right to intervene, with Don Robertson eventually brandishing a red, after initially booking the player.
Verdict: Correct decision
Hearts penalty
Probably the most controversial of the lot.
Tomoki Iwata was penalised for handball eventually after Robertson was advised by VAR to check his pitchside monitor for a potential handball.
As the midfielder challenged for the ball, he appeared to be nudged by his teammate Alistair Johnston, which then saw the ball strike his arm, with his back to the play.
A penalty was awarded to Hearts as a result, but this has to go down as an extremely harsh decision.
As Kris Boyd said in the Sky Sports studio, 'What is he meant to do?'. A baffling call from the officials here.
Verdict: Incorrect decision
Lawrence Shankland disallowed goal
The Scotland international would go on to score an all-important second goal for this team later in the game.
But he thought his 27th of the season had come deep into first-half stoppage time.
After slotting home beyond Joe Hart, VAR found that the forward had strayed offside before scoring, so it was ruled out.
With VAR being totally factual, there can't be any complaints about this call.
Verdict: Correct decision