Barcelona manager Hansi Flick tore into the officiating after his side's 2-0 home defeat by Atletico Madrid in the Champions League, raging over a second-half penalty call and Pau Cubarsi's red card that left his team a man down before halftime.
Flick's anger centred on an incident in the 53rd minute when Barca appealed for a penalty.
Goalkeeper Juan Musso appeared to have put the ball in play from a goal kick before defender Marc Pubill handled it inside the six-yard box to retake the goal kick. Referee Istvan Kovacs waved play on and the VAR crew did not call him to the monitor, sparking animated protests from the home bench.
"I don't know why VAR hasn't been used. The referee ... I think he's brilliant. We all make mistakes, but what's the point of VAR? I just can't understand it. It should have been a penalty, a second yellow and a red card as he already had a booking. This is exactly what shouldn't happen," Flick told Spanish broadcaster Movistar Plus.
Atletico manager Diego Simeone saw it differently.
"It's a matter of common sense," Simeone told reporters.
"The referee saw it as it was. That Marc (Pubill) received what appeared to be a pass from his teammate to start the move, the referee saw it the same way as Marc saw it. Then we can look at as many situations as we like."
Barcelona had already been reduced to 10 men in the 44th minute when Cubarsi was sent off for hauling down Giuliano Simeone as the last man. Julian Alvarez brilliantly curled in the resulting free kick before the interval and Alexander Sorloth sealed the win after the break.
Simeone's side, who have never won the competition, reached the 2014 and 2016 finals but were beaten by rivals Real Madrid on both occasions.
"We have things to improve and learn from... we're happy for the win but there's a long way to go," Atletico's Antoine Griezmann told Movistar.
"We're very far from the semis, we're 90 or more minutes away... we're confident but keeping our feet on the ground."
Barca, semifinalists last season, need to make a huge comeback next Tuesday in Madrid if they are to stand a chance of lifting the trophy they last won in 2015.
"It will be tough there but if anyone can do it, it's us," Barca defender Ronald Araujo told Movistar.