The Italian side had erased a three-goal deficit from the first leg against Real Madrid and the game was headed to extra time until a retreating Medhi Benatia brought down Lucas Vazquez, who just had goalkeeper Gianluigi Buffon to beat near the six-yard box.

Buffon was sent off for protesting the decision in the face of English referee Michael Oliver, and Cristiano Ronaldo converted the penalty in the 98th minute to put his side through 4-3 on aggregate.

Agnelli accused Oliver of bias against Italian clubs, but mostly blamed UEFA for assigning him to the game and not incorporating video assistant referees (VAR) into the Champions League for this season.

"We absolutely need VAR in the Champions League," Agnelli told Mediaset Premium. "This isn't about one or two points, but rather going forward in a massive tournament that brings so much money and prestige, we can't allow these incidents to occur.

"For some reason, the vanity of the refereeing designator [UEFA's Pierluigi Collina] is trying to scientifically prove he is unbiased and keeps assigning referees who are against Italian clubs."

As examples of Italian clubs' suffering with decisions, Agnelli also pointed to Roma, who overcame a 4-1 deficit to eliminate Barcelona on Tuesday, and AC Milan, who crashed out of the Europa League last month after Arsenal were awarded a controversial penalty.

"It's not [only] Juve, but Roma had penalties denied against Barcelona, Milan went out of the Europa League with Arsenal, us tonight," Agnelli said. "If it's a technical problem because UEFA don't have good enough referees, we can offer to help train them.

"When we're in the knockout rounds of the tournament, we need to train the referees up quickly, put good people in charge and help them to bring in VAR.

"A goal-line official behind the line isn't the same thing as an official in front of a video replay. If UEFA are not ready, then they need to train it rapidly, just as Serie A did, plus in Germany, Portugal and elsewhere."

VAR is available in Serie A and will be used at the World Cup this summer, but UEFA have yet to approve it for the Champions League.

Buffon said after the game the solution lay more in referees understanding game situations than VAR, and Agnelli said improved referees also would have thought twice about sending off Paulo Dybala in the first leg.

"Players make mistakes, so do referees, but this official completely lost control of the situation," Agnelli said. "A referee in Madrid for the quarter-final must have seen the first leg, realise the Dybala red card was excessive and understand the various situations.

"The referee tonight was in total chaos. It's a pity, the performance of the boys remains, we confirmed -- as did PSG last season and Roma last night -- proved you can come back from 3-0 down to turn things around.

"Incidents happen, the referee didn't understand the moment at all. The most important thing is we have the technology, it exists and is in use, so we have to bring it into the Champions League.

"The referee tonight, when he sees it back, will be the most disappointed person here to realise what happened."