Manchester United manager Jose Mourinho has stressed the importance of making VAR "perfect" after seeing his side controversially denied a goal on review during their FA Cup win over Huddersfield Town this evening.
Juan Mata appeared to have doubled United's lead on the stroke of half time, only for referee Kevin Friend to eventually disallow the goal after it was referred to the VAR.
However, the initial VAR decision appeared to have been made using inadequate offside lines, and even after numerous replays the decision looked to be a marginal one.
"I prepared myself during the week to control my emotions in relation to a similar situation to the one that happened. You score a goal, you have some doubts over to celebrate or not celebrate. Are you happy or not happy? I was not happy the moment I saw Kevin Friend touching the earpiece, I knew something was going on. That doubt is not the best feeling," Mourinho told BBC Sport.
"If the decision is right I am super happy with that if it goes against me. I don't know [if it was the correct decision]. I just heard a few comments. If the decision goes against my team but is the right decision I am very happy with that because what I want is the truth and sometimes it goes against my team and sometimes in my teams favour.
"But I heard comments that maybe the linesman was right and not the studio. I think it's an experimental period. In Portugal we have it in every match. I'm quite familiar with what the VAR is bringing that's good and bad. They have to kill the bad and make it perfect."
United went on to win the match 2-0 courtesy of a Romelu Lukaku brace, setting up a quarter-final showdown with Brighton & Hove Albion.
