Not for the first time this season, VAR was thrown into the spotlight as Manchester City fought back from 2-0 down to beat Swansea City 3-2 in the FA Cup quarter-final.
But this time it wasn't because a controversial decision was made using the video technology but because it wasn't even in the stadium.
There were incidents in the lead up to two of the City goals. One was a penalty call against Swansea's Cameron Carter-Vickers who produced what appeared a fine challenge on Raheem Sterling but as the City player went down in the box, a penalty was awarded by Andre Mariner. The spot kick was saved but went in off the unfortunate Swansea goalkeeper Kristoffer Nordfelt after he'd made a fine save. But that wasn't the end of it.
Aguero's late winner was shown on replay to be well offside and as City celebrated their comeback, fans and pundits were left to question why VAR was not being used despite the game being an FA Cup quarter final. The fact is, that even though the ground is equipped to use VAR, it is not installed because the Liberty Stadium is not a Premier League ground.
This evening's other tie - Wolverhampton Wanderers v Manchester United - did have the facility to go to VAR which made Swansea's defeat all the more disappointing. For the same reason, there will be no VAR when Millwall take on Brighton & Hove Albion tomorrow (Sunday) in the final quarter final tie of the round.
Guardiola later said he was "sorry" about what had happened. He told the Manchester Evening News: "Honestly, I didn’t watch it. If it was not a penalty and was offside, then I am sorry. We deserved to win in my opinion, but I am sorry.
“They asked all the clubs if they wanted VAR and all round Europe it is there, and here it is not. You have to ask the authorities why it is not here. I ask people why it is in some games but here it is not. I don’t like to lose when the decision is wrong, but referees will make wrong decisions and must be helped. But if we win in that way I am sorry if it was not a penalty and the goal was offside.”
Goals from Matt Grimes and Bersant Celina saw Swansea stun the quadruple-chasing blues and they held a 2-0 lead until midway through the second half. Bernardo Silva got one back for City before that penalty call and then Aguero rounded things off in the closing stages with a well-taken header from David Silva's cross.