The 18-year old has missed the bulk of the 2020/21 La Liga season after undergoing knee surgery at the back end of 2020.
The club have confirmed he will now have a third operation on the problem later this month and he could possibly miss the remainder of the campaign.
His initial period of rehabilitation was due to end at the start of March, but that is almost certain to be extended by at least a month, and Koeman is remaining cautious over his comeback.
“Out of respect for the player, I am not the person to speak about his recovery,” Koeman told an interview with Mundo Deportivo.
“You have to have respect for him and I am not in favour of rushing things.
“When there is an update, we will communicate it from the club.
“The most important thing is that he recovers calmly. He has a lot of future ahead of him and you have to do things right.”
Koeman did hint the Spanish international could see some action before the end of the campaign, with La Blaugrana still fighting on three fronts domestically and in Europe.