Mauricio Pochettino admits he does not like VAR in its current form despite its intervention helping Tottenham beat Chelsea on Tuesday night.
After Harry Kane was upended by Chelsea goalkeeper Kepa Arrizabalaga inside the area during Spurs' 1-0 Carabao Cup semi-final first leg win over Chelsea, an initial offside decision was overturned by VAR as replays seemed to show Kane onside.
However, Chelsea's own footage seemingly shows Kane's upper body was leaning over the line and was therefore offside.
Regardless of the decision, Pochettino feels there is a lot of work to do to improve the system ahead of its introduction into the Premier League next season, and says its use is not clear.
He told Sky Sports: "I don't like it, today we got the benefit but watching the World Cup and La Liga - no one is happy. To get the benefit is nice but I'm not happy to win the game like this.
"I prefer the technology but in a different way and to be clear in the way we use it. I am pro-technology as you can't stop the evolution. When are you going to use it? I don't think it's clear - before we use it all clubs need to agree with ideas. If not it's going to be difficult.
"We still have six months to improve the system - there's a lot of work to do."
He then said in his post-match press conference: "I am not happy with that system, it's a system we still need to agree how we use it. A good example is La Liga, nobody is happy, because nobody knows how the clear way we are going to use it.
"Everyone is complaining now in Spain, from day one. I hope now we have time to develop that system. We need to work a lot between players, coaching staff and the referee. It needs to be a tool To improve the game.
"It was a good decision for Tottenham, but we were waiting five minutes. Some people may say this guy is crazy, but I am telling you when we have benefitted!"
Chelsea dominated the ball and had more of the chances at Wembley, which Pochettino recognised, but the Argentine was delighted with the way his side competed physically after going 1-0 up in the first half.
"Chelsea was good today, of course it is half time. I think we were very competitive, we are happy with that. Chelsea was very good, and we knew they have a lot of quality."
Asked if Spurs deserved the win, Pochettino replied: "I don't know. I am not going to talk for you or for the other people, that is half-time, 1-0 for us, and we need to be ready to compete in the second leg, but it is not about deserve or not deserve.
"The second leg is going to be tough. They have a lot of quality, but what pleases me most is today we were competitive. I am so happy with the performance."