I don't like to win games when decisions are wrong.
A few minutes later, United States global Cameron Carter-Vickers was judged to have fouled Raheem Sterling in the box, even though he won the ball and only then seemed to bring Sterling to the ground.
The Liberty Stadium is equipped for VAR but because other Championship grounds are not, it was not operated for the sake of consistency.
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Swansea said the club was set up to use VAR given their history of being in the Premier League between 2011 and 2018.
Guardiola said: 'If it is not a penalty, and it is offside like the people say, I'm sorry.
Had VAR been applied to non-Premier League stadiums in the FA Cup, the visitors' second and third goals would not have stood.
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For one, a 24-year-old man from Brick, New Jersey has already been arrested in connection with the murder. Police said surveillance video captures the shooter, and the pick-up believed to be the getaway truck.
"That seems a bit unusual considering we were there for seven years and all the technology is placed here to accommodate it".
Matt Grimes calmly slotted the Swans ahead from the penalty spot, before a stunning move on the break saw the impressive Daniel James ran at the defence to open up the space for Bersant Celina, a former City youngster, to curl a wonderful shot past Ederson and into the top corner.
City, fighting back from 2-0 down with 21 minutes to play, had levelled in contentious circumstances too when Swansea defender Cameron Carter-Vickers was judged to have tripped replacement Raheem Sterling in the area and Aguero's penalty hit the post before rebounding in off Nordfeldt for an own goal.
Guardiola said: "You have to say congratulations to Swansea, it was incredible".
"I don't like to lose games when the decisions are wrong, the referees don't want to make wrong decisions and they must be helped".
"But it does not make it any easier when Aguero and Sterling come on, it makes it more hard and in the end we couldn't hold out. The performance was one to be very proud of". But for a long time tonight it looked like that might happen.
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