Luke Shaw claims referee Stuart Attwell told Harry Maguire Manchester United deserved a penalty before opting not to give it.
The decision proved to be decisive as the Red Devils draw 0-0 with Chelsea at Stamford Bridge.
Callum Hudson-Odoi appeared to handle the ball in the box as he and Mason Greenwood battled for possession.
VAR advised Attwell to visit the screen before making a decision on whether or not to point to the spot.
He is alleged to have told United's skipper that a penalty was going to be awarded, but he knew it was going to cause a stir.
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Shaw said: "I think at the time I saw a handball. I didn't know if was Mason or Callum. Didn't even know there was a potential check.
"I don't know why they stopped it if it's not going to be a pen.
"The ref even said to H [Harry Maguire] if it's a pen then it's going to cause a lot of talk about it after.
"So I don't know what happened there. H got told it was a pen. I'm not sure.
"I don't understand. If it's going to stop you think it's going to be a pen because we had the ball, we were attacking.
"I'm not going to moan about it because I don't think either team did enough to win."
United boss Ole Gunnar Solskjaer claimed it was "100 per cent" a penalty.
Although he stopped short of revealing what Attwell had told his players insisting he "doesn't want to cause controversy" - but Shaw had already made it clear.
Blues boss Thomas Tuchel claimed it was a "high quality game" but felt as if Greenwood was the man who handled the ball - not Hudson-Odoi.