Possible penalty: Handball by Grealish
What happened: Manchester United were on the attack in the 29th minute when Aaron Wan-Bissaka tried to head the ball into the centre of the box. The ball appeared to flick off Jack Grealish before Manchester City were then able to clear their lines. As play continued, there was a review for a possible penalty.
VAR decision: Penalty, scored by Bruno Fernandes.
Ilkay Gundogan raises the FA Cup trophy in front of the crowd at Wembley Stadium after scoring both of Man City's goals vs. Man United.
VAR review: It's a classic example of a modern handball offence, and a situation like this has usually been judged as a penalty for several seasons now.
There are exemptions that could have saved Grealish, such as proximity to the play of the ball and expected body position for his movement. However, the City midfielder's left hand appeared to move up toward the ball before it flicked his fingers. Was that a natural part of his body movement? Or a handball offence? Some referees will disagree this should be punished, but at the top level, with VAR, a penalty is always likely to be given -- especially as the hand has moved above shoulder level.
Even though Grealish had no intent to handle the ball, or to make his body bigger, and clearly wasn't fully aware of the ball's location, it was that instinctive movement of the arm that left the VAR, David Coote, with little place to go in law.
"I don't even think it's a penalty," Grealish told BBC Sport. "I wasn't even looking at it, I turned and it hit my arm but [Ilkay] Gundogan saved me [by scoring the winning goal]."
You have to feel for Grealish, as when the ball drops over his head to Wan-Bissaka, he is turning to follow its path and isn't expecting the United player to immediately play it back at him. No one in the game really wants a situation like this to give the opposition a penalty, but in reality officials are hamstrung by the law.
There are some similarities to the penalty awarded to Crystal Palace against Aston Villa at the start of the season, when the ball hit the arm of defender Lucas Digne from close proximity and a penalty was awarded through a VAR intervention. The Independent Key Incidents Panel judged that to be an incorrect VAR intervention, as Digne had his back to the ball and was hit at point-blank range.
Grealish was facing the ball, and his hand moved up to it, while Digne's arm position didn't change. It does show how these decisions remain subjective and how even small differences can suggest a different outcome should have been reached.
Penalties such as these are certainly less palatable when there is only a flick of the fingers rather than the ball fully hitting the hand. But in a world with VAR, with the current interpretation, a player is going to concede a penalty for this.
UEFA's new Football Board, set up to advise European football's governing body on matters including the laws, says there should be a more relaxed interpretation of handball. But the application of this law in England is far less strict than in other countries, and any amendment is more likely to bring other leagues closer to English football rather than having any huge impact here.
Possible red card: Casemiro challenge on Akanji
What happened: In the 12th minute, Casemiro and Manuel Akanji challenged for the ball. Referee Paul Tierney gave a free kick against the Manchester City defender -- but in fact the VAR initiated a review for a possible red card against Casemiro.
VAR decision: No red card.
VAR review: A quirk of protocol, because even though the VAR has identified there has been a foul by Casemiro -- so the referee has given the free kick to the wrong team -- he cannot change that on-field decision without advising a red card.
So, if the VAR does think there has been a red-card offence, the game restarts with a free kick to City. But if he doesn't think it's a red card, play begins with the incorrect free kick to United.
If a red had been shown by Tierney, it wouldn't have been overturned. But of course he gave the free kick the other way, so surely that's a clear and obvious error? The VAR still have to judge this as a definite red-card offence, rather than just send the referee to the monitor for getting the free-kick decision wrong.
It was definitely worthy of a yellow card -- again, VAR protocol prevents an intervention for a caution -- but doesn't cross the threshold for a VAR intervention.
We have seen many challenges across the season where a player has caught an opponent above ankle level, but if there is no force or intensity, then the VAR doesn't intervene -- that's the case here.
It's why fans get so frustrated with VAR; if it can give the Grealish handball, why not the Casemiro red card? Much of this comes down to the intricate guidelines around handball, which have attempted to cover every specific situation. For serious foul play, there hasn't been such an overhaul, so perhaps referees make decisions more to their own view rather than following strict application of a law.
Possible penalty: Fred challenge on De Bruyne
What happened: In the 39th minute, Kevin De Bruyne went down in the box under a challenge from Fred. The Belgium international was adamant he should be awarded a penalty, but Tierney wasn't interested. The VAR had a lengthy check for a possible penalty.
VAR decision: No penalty.
VAR review: The same can be said of this incident, which if it had the same layers of interpretation as handball would surely be a penalty.
Fred appears to be stepping across the ball to shield it when he brings down De Bruyne. Is it a foul, or two players coming together?
It's a decision where if a penalty had been given, the VAR wouldn't have gotten involved to overturn it. But at the same time, with the high bar for intervention in English football, it again doesn't reach the threshold of a clear and obvious error.
There are similarities to another incident involving De Bruyne in April, when Arsenal midfielder Thomas Partey was trying to shield the ball in front of goalkeeper Aaron Ramsdale. De Bruyne kicked Partey, and the free kick was given to Arsenal despite the claims for a penalty.
In that case too, the VAR did not intervene to change the on-field decision -- which was supported in the postmatch review by the Independent Key Incidents Panel.
This is a stronger claim, however, as Fred appeared to catch De Bruyne rather than it being the other way around.