Manchester City are hopeful Alvaro Negredo will only be out for two months after the striker broke his foot.
The 28-year-old, injured in a friendly against Hearts on Friday, posted a picture on Instagram of his right foot in a protective boot.
"I want to let you know that it's going to be hard for the next few months," he wrote. "I fractured my 5th metatarsal and will be out a few months.
"I will be back stronger than ever. I will return with a vengeance."
Reports had claimed that Negredo would be out for three months but City officials believe he could be back before the end of September.
Manager Manuel Pellegrini had been willing to listen to offers for the Spain international, who was not part of their World Cup squad.
But Negredo said last week: "I don't want to leave City. I'm very happy and very settled here.
"I had a difficult end to the season and that's why there has been a lot of talking but I've been very happy here from the first day I arrived."
Negredo scored 26 goals before the end of January after signing from Sevilla in the summer of 2013.
But a shoulder injury, combined with a loss of form, led to 16 scoreless appearances.
Negredo limped out of City's 2-1 friendly win at Tynecastle shortly before half-time.
The club flew to Kansas for the start of their pre-season tour of the United States on Monday.