Manchester City striker Sergio Aguero was hospitalised with a suspected broken rib after being involved in a auto accident in the Netherlands, two days before his team's biggest Premier League game of the season.
"The City forward was in Holland on his day off and has sustained injuries".
Guardiola, after confirming the striker suffered a broken rib in a vehicle accident, added: "He had a day off".
"I don't like to train everyday because I think players need to rest mentally and physically, and they can enjoy their lives".
The English Premier League (EPL) club confirmed in a statement that Aguero will return to England on Friday to be assessed by the club's doctors.
The Spanish manager said he did not know how long Aguero would be sidelined for, and added that he only discovered his striker was in the Netherlands early on Friday. Fortunately, he will come back and recover as soon as possible.
Guardiola confirmed he is not going to impose more rules that force City's players to stay at home on their days off.
"I want my players to have fun". If they decide to go there, they decide to go there.
"We have enough rules".
He'll now have to wait to pass that tally and it has been reported City will be without his services for around two months following the crash in the De Boelelaan area of Amsterdam.
Aguero, who has scored 176 goals for the English club, on Thursday posted a picture of himself with Maluma on his official Instagram page. "Everyone @ Independiente is with you in this hard moment".
City had already been dealt an injury blow this week when defender Benjamin Mendy was found to have ruptured the anterior cruciate ligament in his right knee.
City faces Chelsea at 12:30 p.m. Saturday in Premier League action at Stamford Bridge in London.
And the manager confirmed that Aguero would be unavailable for Argentina for their final World Cup qualifiers against Peru and Ecuador, with the Albiceleste now outside the automatic qualifying places for Russian Federation.
City are level on 16 points with Manchester United at the top of the table with Chelsea in third place on 13, and Aguero is one goal away from equalling Eric Brooks' all-time club record of 177 goals in all competitions.