Monaco coach Leonardo Jardim called his side's Champions League defeat "a grave injustice," as Ricardo Carvalho said Juventus' penalty should have been given as outside the box.
Juventus were gifted an opportunity to score in the 55th minute when Carvalho brought down Alvaro Morata at the top of area as both players chased a lofted ball.
Arturo Vidal delievered the spot-kick and Juventus prevailed 1-0 in the first leg of their quarterfinal in Turin.
Jardim, however, argued that the penalty should never have been given.
"This result is a grave injustice," said the Monaco coach. "The penalty should not have been awarded."
Carvalho's argued that his contact with Morata began outside the box and therefore should not have been a penalty.
"Both myself and Morato were both looking for the ball and I think after you have the contact but I have the idea that it was outside the box," Carvlho said.
"It's a contact that I can't avoid, I'm looking for the ball and after that you have a contact, a small contact, but I think it was outside of the box."
When asked if he though his side deserved more, Jardim said: "Of course. It was an even game. We dominated the first 20 minutes of the first half and the first 20 minutes of the second half. We had hoped to come away with a better result.
"It's going to be completely different in Monaco -- we will give a different impression of ourselves in our home game to make it through.
We showed we're an organised, good team and we created real problems for Juventus. At this level, you've got to have a certain degree of effectiveness and I think we showed that. We created good chances going forward."