LONDON -- It really should all be about Olivier Giroud. The France forward, called in from the cold by Chelsea manager Frank Lampard, scored one and helped make the other to inspire his team to a crucial 2-1 London derby win against Jose Mourinho's Tottenham, but thanks to another episode of VAR farce, the story of this game was about a man in a video booth rather than a guy on the pitch.

There have been plenty of VAR controversies during the system's debut season in the Premier League, but none have been quite so embarrassing, and potentially influential, as the failure to issue a red card to Spurs midfielder Giovani Lo Celso following his second-half foul on Chelsea's Cesar Azpilicueta.

Before the end of the game, Premier League sources were confirming that Professional Game Match Officials Limited (PGMOL), the body in charge of referees and VAR, had accepted that they had got it wrong. When the system designed to clear up refereeing mistakes is unable to get it right after reviewing several slow-motion replays, it points to serious flaws in the management and implementation of VAR.

"I hate to call for red cards," Chelsea manager Lampard said after the game, when asked about Lo Celso's challenge. "But that was a leg-breaker."

Lampard had a point. Certainly, 'foul' doesn't do the challenge justice. Lo Celso, whose season-long loan from Real Betis was turned into a permanent deal last month, rode a challenge from Azpilicueta on 52 minutes, but then stamped on the Spaniard's shin as he planted his foot. Azpilicueta writhed in agony on the pitch and underwent lengthy treatment, with television footage showing stud marks on his shin.

Match referee Michael Oliver had failed to spot the severity of the incident, but unsurprisingly, it was immediately reviewed by VAR. It should have been a straightforward decision for David Coote, the Video Assistant Referee for this game at VAR HQ at Stockley Park. But Coote, who has taken charge of 23 Premier League games and never issued a straight red card, inexplicably judged the challenge to be not worthy of a sending off, with the initial Premier League briefing suggesting that it was not a clear and obvious error because the VAR didn't feel there was anywhere else for Lo Celso to put his foot.

Coote's mistake only highlighted the folly of referees being advised by Mike Riley, the general manager of PGMOL, not to consult the pitchside monitor for reviews, instead leaving them to the VAR in Stockley Park. But it also led to a deluge of criticism from former players and ex-referees in the media and on social media in the minutes after Lo Celso had been let off the hook. Will we ever know whether the outcry prompted PGMOL to admit their mistake?

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Ian Wright, Rio Ferdinand, Cesc Fabregas, Robbie Savage and Dion Dublin all quickly expressed their shock at the decision, while Keith Hackett, England's former senior referee and Riley's predecessor as GM at PGMOL, went further by suggesting the current regime in charge of officials don't even know the Laws of the Game.

"Come on David Coote VAR," Hackett tweeted. "That is a red card every day. It's not a difficult decision. Lo Celso should have received a red card. Now I want to know who is the person at the centre of the PGMOL statement. I suggest that he goes to theifab.com and updates himself on LOTG [Laws of the Game]."

When a former top-level referee is questioning the competence of the current officials, it is hardly surprising that supporters, players and managers have lost faith in them and VAR. Chelsea fans chanted "F--- VAR!" during the game and Azpilicueta admitted his surprise at the failure of either Oliver or Coote to dismiss Lo Celso.

"I'm not a player that likes to be on the floor because I'm tough but it was not my fault because it was a clear stamp on my shin, I felt it straight away," Azpilicueta said. "I was surprised it was not a red card, not even a yellow card. Obviously everybody makes mistakes but when you have a lot of replays, it could be easier."

Sadly for PGMOL, this is not the first instance of VAR getting it horribly wrong this season. Just five days ago at Stamford Bridge, Manchester United captain Harry Maguire escaped a red card when VAR judged that his studs-up reaction following a tangle with Michy Batshuayi was not worthy of dismissal. Tottenham's Son Heung-Min was sent off following a similar incident with Chelsea's Antonio Rudiger earlier this season -- a decision which highlights the inconsistency shown by VAR this campaign. But the Lo Celso incident has taken it to a new low and it may prove to be a tipping point that prompts PGMOL to review their use of the system.

"Everybody knew they made a mistake," Lampard said. "We have the monitor and can view it. I was just waiting for the red to be shown because it was a tackle that endangered the player.

"It's just not good enough. Saying afterwards that they didn't get it right is not good. They took almost two minutes, but it was so wrong today and another question mark over VAR."

The question marks are growing. VAR is supposed to make the game fairer and cut down on controversy, but it is being mismanaged, with the responsibility for decisions taken away from the referee on the pitch. Changing that will not solve everything, but it will be a good start.