Pep Guardiola fears Kevin De Bruyne could be out into the new year with the hamstring injury sustained in Friday’s Premier League win at Burnley, and has described it as a “big blow”.

The 32-year-old was forced off after 28 minutes of the season opener in a recurrence of the problem that caused his first-half substitution in June’s Champions League final victory over Internazionale.

Guardiola said: “It’s serious – a big blow, really tough for us. We have to decide whether he has surgery or no surgery but it will be a few months out. In the next days we will decide on surgery. The injury is a big loss, Kevin has specific qualities. You can lose it for one or two games but for a long time it’s really tough for us but you have to look forward.

“We have alternatives with different skills, different talents. It’s another opportunity [for others] – life gives you that. I’m pretty sure they will take it.”

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Guardiola’s trusted physician Dr Ramon Cugat is advising the club regarding De Bruyne. “Ramon saw the images,” Guardiola said. “He didn’t personally [do anything] and they have two or three doctors who have the same opinion on what we have to do.”

Phil Foden may be Guardiola’s initial choice to replace De Bruyne. “He can play there but play outside as well,” the manager said. “We have alternatives – Mateo [Kovacic]. The club gave me a really good squad and we’ll find a solution.”

Rodri underlined how crucial the Belgian is. “He’s one of the most important players of the club for sure,” the midfielder said. “We’re going to miss him a lot. We’re going to try to support him in that moment when nobody wants injuries. I saw him the other day and he was positive, he wants to come back, he’s an experienced player. He knows that he doesn’t need to run fast to come back, he has to recover. We’re going to miss him but I can tell you that we have a big squad.”

City are interested in West Ham’s Lucas Paquetà. The manager was asked whether De Bruyne’s injury would cause the club to offer him a signing to cover for his absence. “We will see,” said Guardiola.

The 18-year-old Rico Lewis is an alternative to replace De Bruyne given his ability to operate in a defensive-midfield hybrid role. The academy graduate has signed a new five-year deal. Guardiola said: “It’s incredible for us – for the club to have a player from the academy who will be here a long time with us. He is amazing.”

City are in Athens for Wednesday night’s Uefa Super Cup final against Sevilla, aiming to claim their fourth trophy of the year after last season’s treble. “We are here, we are hungry to compete and challenge ourselves and prove ourselves,” Guardiola said. “If someone wants to take out three crowns, they will have to fight to take it. Still we want to defend what we won last season.

“For Man City we never had this trophy because you have to win the Champions League or Europa League to be invited.”

Bayern Munich wish to sign Stefan Ortega, City’s No 2 goalkeeper. “It would be a problem to lose him – first for the quality,” said Guardiola. “We don’t want to lose him. We need him but like in any cases it depends on three parts. If we lose Stefan two weeks out of the market, we have to go to pick up a keeper and it’s not easy now.”