How VAR will be used in the Champions League

That’s because it will be one of the first two Champions League matches – the other being Roma's home game against Porto  – in which the Video Assistant Referee (VAR) will be in operation.

While this will be the first time VAR has been used in a European match in England, it has already made its debut at Old Trafford, in last month's Emirates FA Cup tie against Reading.

On that occasion, the system led to the award of a penalty scored by Juan Mata; the same United player had previously been on the wrong end of a video-assisted decision, when he had a goal contentiously ruled out for offside against Huddersfield last season.

WHAT DOES OLE THINK OF IT?

Ole Gunnar Solskjaer feels it hasn’t changed anything in terms of United's preparations for the big game but admits he has mixed thoughts about VAR.

"VAR has been part of football lately now and players are getting used to it," our caretaker manager told reporters in his press conference on Monday.

"We had it in the FA Cup, we've had some introduction to it. It's a good thing if it's a clear and obvious decision that has to be made, but it's still opinions that the referee has to make.

“For me, I like to have the discussion the day after [the match]. Was it a penalty, was it not a penalty? Like football has always been. But it's not going to be an issue.”

WHO WILL BE THE VAR?

Massimiliano Irrati will assume the role tonight, as part of an Italian team of officials led by referee Daniele Orsato.

Irrati was the main VAR for 14 matches, including the opening game and the final, at last summer’s World Cup – more than any other official.

HOW WILL VAR WORK?

Video Assistant Referees (VAR) will be introduced into the UEFA Champions League from this round. The VAR will be used in order to support the referee when making decisions concerning four match-changing situations:

• Goals
• Incidents in the penalty area
• Red cards
• Mistaken identity

The VAR will inform the referee when there is evidence of a clear and obvious mistake in one of these match-changing situations. The referee can then use the review area next to the pitch to take a final decision. The VAR is also able to take into account any infringement that could have taken place in the immediate build-up to the incident (the attacking phase of play).

Decisions like offside or whether a foul was committed inside or outside the penalty area will be recommended to the referee directly by the VAR and no on-field review necessarily takes place in such cases. The on-field review process will be communicated within the stadium using either the stadium screens or the public announcement system. 

WHY HAS IT BEEN INTRODUCED NOW?

UEFA decided to fast-track its introduction into this season’s competition from the knockout stage, after initially deciding to bring it in from the start of next term.

UEFA’s chief refereeing officer Roberto Rosetti, who has led the project for the introduction of VAR in the Champions League, has confirmed the decision was made following successful technological testing and the training of referees over the last few months.

"We are convinced that it will be beneficial for our competitions as it will provide valuable help to match officials and will allow to reduce incorrect decisions," said the Italian, who took charge of the Euro 2008 final between Germany and Spain.

"We held various courses over the last few months with our top referees and they welcome any steps to ensure that, ultimately, the correct decision is made.

"We had successful technological testing and trained the referees over the last few months. We have then tested VAR at selected matches and finalised preparations on all operational aspects. Now we are ready to implement VAR in the UEFA Champions League Round of 16." 

WHEN VAR COULD HAVE HELPED US

We recall three major incidents in the Champions League where decisions went against us and the presence of VAR could potentially have changed the outcome…

2004: Paul Scholes’s disallowed goal v Porto
It was a decision which ultimately proved costly for the Reds, who were beaten 3-2 on aggregate by the Portuguese side after a 1-1 draw at Old Trafford. Scholes had given United the lead and should have doubled our advantage on the stroke of half-time but his strike was ruled out for offside by the Russian officials. Television replays showed the decision was clearly incorrect. VAR would have certainly allowed the goal on this occasion and it could well have sent United through to an eighth successive Champions League quarter-final.

2009: Darren Fletcher’s red card v Arsenal 
The midfielder was sent off by the aforementioned official Rosetti, who ruled that the Scot had fouled Cesc Fabregas as he raced in on goal during United’s 3-1 win in the second leg of the semi-final at the Emirates. Replays showed that Fletcher clearly poked the ball away before making marginal contact with Fabregas. The harsh dismissal meant he missed the final against Barcelona in Rome.

2013: Nani’s red card v Real Madrid
There was a huge moment of controversy in our last-16 second-leg clash against the Spanish giants at Old Trafford six years ago. With the Reds 1-0 up and on course to reach the quarter-finals, Nani was shown a straight red card by Turkish referee Cüneyt Çakır for a challenge on Alvaro Arbeloa. It served as a significant turning point as goals from Luka Modric and former United star Cristiano Ronaldo turned the tie in favour of Real Madrid, who progressed 3-2 on aggregate. Many thought the challenge from Nani was only worth a yellow card. Might VAR have advised the referee to act differently? We’ll never know.

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