Manchester City reached the semifinals of the FA Cup on Saturday but were knocked off the top of the Premier League 24 hours later when Liverpool narrowly beat Fulham.
Aguero's late victor 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.
Nuno Espirito Santo's side defeated Ole Gunnar Solskjaer's Manchester United in an underwhelming performance from the Red Devils, otherwise resurgent under the Norwegian.
In the first match, Watford edged a narrow 2-1 win over Crystal Palace as Andre Gray came off the bench to net a late victor at Vicarage Road.
Wolves held on to win a game it dominated, but Swansea couldn't protect its 2-0 lead against a City side that benefited from two refereeing mistakes.
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Morrison says religious freedom has to start with the right to worship and meet safely without fear of violence. We're a club, we do our things but, nah, that's just wrong in every way possible, ' one said .
City made a fine start and went close three times in the first 15 minutes, but Swansea capitalised soon after - Grimes coolly dispatching a penalty after Fabian Delph tripped Connor Roberts.
Swansea then carved City open with a slick passing move and it was superbly finished off by Celina. 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.
"City had chances of course, you can't deny if you look at the game that they deserved to win", Potter said.
"I was happy to score and make up for the penalty miss in the week", Celina said. VAR was only in use at Premier League stadiums in the quarterfinals.
Championship side Millwall host Premier League side Brighton on Sunday.
Guardiola, whose side have already won the League Cup and are through to the quarter-finals of the Champions League, added: "When you fight for all the titles you don't have rest and every three days there is a game, it is so, so healthy to win these kind of games". Javi Gracia's men, who are in the last four for the second time in four seasons, having lost to Crystal Palace at Wembley in 2016.