Ernesto Valverde was unhappy with the VAR system as 10-man Barcelona surrendered their 100 per cent start to the season in an eventful 2-2 Catalan derby draw with Girona.
Barca had defender Clement Lenglet sent off 10 minutes before the break at the Nou Camp after he caught Riera Pere Pons with his elbow with referee Gil Manzano producing a red card after being invited to view video footage of the incident.
However, manager Valverde, whose side was leading 1-0 at the time, was not convinced the officials had got it right.
He told LaLiga TV: "Well, there's a clash, that's clear and there's an elbow, we have seen that in the photo. It's the first red card that (the) person who is on the receiving end of it says sorry, and that's Lenglet.
"The VAR is there to give out justice and I don't think it was a red card. There's an impact maybe and Lenglet has made a strange gesture, but I don't think it's a red card at all.
"The referee had looked to see if the opponent had committed a foul."
Lenglet's premature departure turned the game on its head as Cristhian Stuani cancelled out Lionel Messi's 19th-minute opener on the stroke of half-time and then doubled his tally six minutes into the second half as the 10 men wilted.
However, Barca regained their composure and got their reward when central defender Gerard Pique headed them level with 27 minutes remaining, sparking a late onslaught which ultimately came up short.
Valverde said: "The red card really changed the game. We were dominating and then after the red card, it's not that we didn't have control then either.
"We had the bad luck to concede the equaliser right at the end of the first half and then at 2-1 down, we had to try to get back into the game."
Girona boss Eusebio Sacristan was delighted with the way his players took advantage of their opportunity when it arrived, and admitted it was "a luxury" to have Stuani among his ranks.
He told his post-match press conference: "Christian Stuani brings us a lot of quality, commitment and experience.
"He knows perfectly how to play with the body, how and when to finish – it's a luxury for us to have him at Girona."
Despite having seen his side take seven of the last nine points on offer, Eusebio insisted they cannot afford to rest on their laurels.
He said: "We are very happy because we have competed and achieved points looking at the calendar we have had. But every game at Primera division is difficult, and we have to continue working to continue improving."