France lost 2-0 in Paris on Tuesday in a game in which the Spanish side benefited twice from crucial video assistant referee decisions.
A goal against the Spanish was disallowed after it was ruled offside in consultation with the video and a Spanish goal disallowed by the referee for offside was overturned and ruled a goal after a review.
For the French, who decided to trial video assistance for the first time at the friendly match, the outcome was galling, even though fans and players recognised the video calls were correct.
"If it allows you to correct mistakes, as has been the case here, even though it went against us, that seems to me to be good for justice in sport," said French coach Didier Deschamps.
Spanish counterpart Julen Lopetegui predictably had no arguments with how the decisions played out.
"The refereeing resolved the two actions in a fair manner," he said.
French striker Antoine Griezmann headed in what appeared to be the opening goal at the Stade de France shortly after half-time, triggering delight in the stands and on the field after France had been on the back foot throughout the first period.
The referee then consulted the video assistant and about 30 seconds later the goal was chalked off for offside.
It was the reverse when Gerard Deulofeu scored Spain's second goal 12 minutes from time.
The new system might be more fair, admitted French captain and goalkeeper Hugo Lloris, "but it also kills off the joy of scoring a goal".
"It is a pain because you have to wait before you can celebrate the goal."
The 80,000 spectators at the stadium were left out of the process with no video slow-motion screen to view and saw only the hand gestures of the referee, framing the shape of a TV screen, to show that he wanted a video review.
"That dehumanises the game a bit and can detract from the spectacle," said former referee Bruno Derrien.
"Football is about sentiments, including that of injustice. Video takes responsibility away from the assistant referees.
"If I was an assistant I wouldn't lift the flag to call offside anymore because you have video to decide all that."
Use of technology to assist referees – favoured by FIFA president Gianni Infantino – was first introduced in the 2012 Club World Cup to determine whether the ball had crossed the goal-line in scoring situations.
Critics say the latest development signals a creeping-in of technology, which football has been slow to embrace in comparison with sports such as cricket and American football.
For Pascal Caribian, head of refereeing at the French Football Federation, there should be no rush to judgment about video assistance, which is undergoing a two-year trial with a view to possible introduction at next year's World Cup in Russia.
"It is really necessary to have a large number of games before you judge," he said, saying it was not by chance that FIFA and IFAB, which oversees the rules of the game, have asked for a two-year trial period.
Croatian former playmaker Zvonimir Boban, FIFA deputy secretary general, said high-profile games like Tuesday's friendly were a prime chance for testing and honing.
"We are very happy that the test went well in the game," he said in a statement.
"We know that there will be other tests, which can be not so positive like this one.
"But the test in France showed us one more time that the use of video assistant referees will make the game for sure more honest and this is what we want to achieve."