Villa are still on the hunt for their first Premier League win of the season as they suffered a late defeat to Oliver Glasner’s Nottingham Forest.
Emery, however, believes things should have gone differently, and that midfielder McAtee, should have seen red for a rash challenge on Ian Maatsen.
Igor Jesus’ 88th minute winner came when Villa were playing with 10 men after Maatsen limped off with Villa having made all their substitutions.
Speaking after the game, Emery said: “When we equalised, the match could change, but we finished with Ian Maatsen injured.
“And with 10 players we conceded so many chances in the last minutes and they scored the second goal and they deserved it.
“But after watching it on TV, I think the VAR referee should call the referee because it’s a clear tackle from behind and for me it should be a red card.
“Of course, they deserved it. They played the second half, deserved to win. But the decision of the referee should be different.
“After the injury of Maatsen we’re finishing with 10 and, of course, we can have one injured player on the field. But in this case it was a tackle and he injured the player. Of course, he didn’t want to injure our player.
“But if we can watch it through the TV, it’s a VAR action, and to call the referee it should be a red card and maybe finishing with 10 v 10 was different in the match.
“But it’s not an excuse for how we played in the second half. We played so, so poor, and this is my responsibility.”