​Barcelona players returned to the club on Monday for medical checks ahead of the start of pre-season, including Ronald Araujo and Frenkie de Jong who are not due back for training yet after their involvement at the World Cup.According to Marca, there’s bad news regarding De Jong as he has a knee injury that may see him sidelined for some time.AdvertisementAdvertisementAdvertisementThe report says that the Dutchman is due to undergo further tests in the coming days but there is “great concern at the club.” Barcelona are said to “fear the worst” and there is a suggestion he could be out for four months.The club and player now face a nervous wait for a final diagnosis to be made and a decision on how much time De Jong will miss to be confirmed.The loss of the midfielder would certainly be a blow ahead of the start of the 2026-27 season, particularly with Barcelona having so many players still involved at World Cup 2026.De Jong is also having a tough time with injuries currently. He missed large part of last season with an ankle injury and is now potentially facing more time on the sidelines.