Barcelona coach Ernesto Valverde has said it is "absurd" that technology has not been implemented in Spanish football after match officials failed to spot that Lionel Messi's shot against Valencia on Sunday had crossed the line.
Jordi Alba's late equaliser earned Barca a draw at the Mestalla, keeping both teams' unbeaten records intact, but things could have been different had Messi's first-half strike counted.
Valverde refused to complain too much after the game, pointing out Barca had benefited from a similar situation when the ball went out of play in the buildup to Gerard Deulofeu's goal against Malaga.
However, speaking at a news conference before Wednesday's Copa del Rey game against Real Murcia, he said: "What is absurd is that people in the top row of the stadium can see that the ball is in and those below them can't.
"From the assistant's view, he couldn't see it. I couldn't, either. But from the moment I saw what happened, I knew it was in because of how Leo celebrated, how the goalkeeper had his head down... [Martin] Montoya went to get the ball to take it back to the middle of the pitch.
"It's crazy that in such an important game, and at an important moment, the referee doesn't see it when there are 40,000 people that knew it was a goal. Every year there's an episode like this.
"Goal-line technology has to be introduced, of course. With the technology we have in our hands and what is used in other sports and other leagues, it's absurd that it doesn't exist here."
La Liga president Javier Tebas has said video assistant referees [VAR] will be introduced gradually next season, although there are no immediate plans to implement goal-line technology.
And Valverde was keen not to put too much blame on officials, saying: "They make mistakes, but the level of refereeing in Spain is good.
"We always want decisions to go in our favour, but I don't question the level of refereeing. It's tough."
Valverde was responding to comments made earlier on Tuesday by the head of the Spanish football federation's referee committee, Sanchez Arminio, who spoke in support of Ignacio Iglesias Villanueva, the ref at Valencia.
"Referees make mistakes, and that has to be accepted," he said. "The Messi goal was seen clearly on television, but it's very difficult to see it on the pitch.
"Iglesias Villanueva's refereeing was very good, it was just that one moment. And if he says that he didn't see it, then it doesn't matter.
"It's not easy for people to understand that what's seen on the television is not always the same on the pitch.
"I have spoken with him and I know what he is going through. It isn't fair that he is being treated the way he is."
Barca return to action on Wednesday in the second leg of their Copa del Rey tie against Real Murcia.
With a 3-0 advantage from the first leg, Valverde has given eight first-team players, including Messi, Andres Iniesta and Luis Suarez, the night off.
"We've got a lead so some players will have a rest, but the idea is still the same," the coach said. "We want to play well and go through."