The accident occurred at around 11pm as Aguero travelled back to an airport in a taxi after attending the gig, performed by Colombian singer/songwriter Maluma.

Guardiola said: "I think days off are to be happy. I want the players to be happy. Always I am a manager who doesn't like to train every day.

"I think the players have to rest mentally and physically. They can enjoy their lives. I want my players to have fun. If they decide to go there, they decide to go there. It is okay for me."

Aguero is understood to have been hurt when the taxi came off the road and hit a post. He was treated in hospital and was due to arrive back in Manchester for further assessment by club medical staff on Friday afternoon.

Guardiola said he did not know how long he would be without his most prolific forward but he would definitely miss the leaders' Premier League trip to champions Chelsea on Saturday. He said Aguero would also be unavailable for Argentina's crucial World Cup qualifiers against Peru and Ecuador next month.

Guardiola, speaking at a press conference, said: "He cannot play tomorrow and the international break - maybe he was selected for Argentina but he cannot go there.

"We will see. I don't know the answers. The first impression we have is that he has a broken rib but exactly how many days he will be off, I don't know right now."

Aguero, 29, had started the season impressively, scoring seven goals in eight appearances to move within one of equalling Eric Brook's club record 177.

Aguero was reported by Spanish sports newspaper AS to have told Argentinian station Radio Metro: "The taxi driver did not see the curve and skidded. And when he skidded, we hit the pole. I broke my rib, now I'm resting. It hurts me badly. I'll be discharged in a little while."

News of Aguero's accident came after further bad updates on injuries to left-back Benjamin Mendy and captain Vincent Kompany.

Mendy has ruptured an anterior cruciate ligament and is facing a lengthy spell on the sidelines.

Guardiola said: "Mendy will be operated on this afternoon in Barcelona. He will be out until our semi-finals of the Champions League."

Kompany has missed the last six games with a calf injury and remains out of action despite being called up for international duty by Belgium.

Guardiola said: "He only made one training session with us since one month ago. I spoke with (Belgium coach) Roberto Martinez. He is travelling there to make a meeting with the Belgium doctor but he is coming back. Of course he cannot play for Belgium."