Garcia's side defeated Udinese 1-0 at the Stadio Comunale, thanks to a disputed header from Davide Astori.
The defender's effort came back off the underside of the crossbar and bounced on the line before Udinese goalkeeper Orestis Karnezis gathered the ball.
The goalline official decided the whole of the ball had not crossed all of the line, but match referee Marco Guida overruled his colleague and the goal stood.
Despite being the beneficiary of the controversy, Garcia believes match officials need more assistance to make key decisions.
"I have always said that we need technology to help the referees, as with goal-line technology this would not have been an issue," he told Sky Sport Italia.
"We need goal-line technology because the assistants have to look at everything in the box, not just the goalline.
"Having said that, the goal-line referee seemed well placed to see the ball was in. At the end of the day, the referee has the final say."
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