The absence of Aguero for the Chelsea match is another blow for Guardiola, coming a day after City confirmed that left back Benjamin Mendy had ruptured the anterior cruciate ligament in his right knee.
The 29-year-old Argentine was in a taxi going to the airport after watching singer Maluma perform when the accident happened.
Speaking on the accident, Aguero had told an Argentine radio station that the taxi driver didn't see the curve, and the auto skidded before crashing into the post.
Manchester City striker Sergio Aguero has reportedly suffered injured ribs after the Argentine forward was involved in a auto crash in Amsterdam, media in Argentina reported on Friday.
Pep Guardiola insists Sergio Aguero has nothing to apologise for after being injured in a auto crash in Holland on his day off.
Aguero had earlier posted a picture of himself on his Instagram account seated in the back of a vehicle thanking Colombian singer Maluma, who was also in the photo, for the invitation.
Amsterdam police spokesman Frans Zuiderhoek told AFP that officers attended an accident in the city at around 11:00pm (2100 GMT) on Thursday after "a taxi-cab hit a lamp-post".
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The Premier League is back for another weekend of action with some massive battles at both the top and the bottom of the table. Three wins from three matches have last season's Championship champions in comfortable 10th place.
He said: "I only knew this morning when I woke up". It was an accident. "Fortunately he'll come back and recover as soon as possible".
"I think days off are to be happy", Guardiola told reporters. How we react is what I want to see.
Initial reports suggest AgueroÂ may have suffered broken ribs, which could rule him out for around two months.
Guardiola confirmed he is not going to impose more rules that force City's players to stay at home on their days off.
City faces Chelsea at 12:30 p.m. Saturday in Premier League action at Stamford Bridge in London.
Aguero has made an impressive start to the 2017-18 campaign, scoring seven goals in eight games for Pep Guardiola's men.
However, City areÂ yet to comment on the nature of the Argentina international's injuries.
The worldwide break follows the weekend's Premier League matches with Aguero in Argentina's squad for their last two World Cup qualifiers against Peru and Ecuador on October 5 and 10.