Casemiro is a doubt for Real Madrid's Champions League semi-final first leg against Manchester City next week.
The midfielder has been a near ever-present for Carlo Ancelotti's side this season, making 42 appearances in all competitions.
After being ruled out of his side's dramatic 3-2 victory over Sevilla on Sunday through suspension, Casemiro was expected to return to the fray when Real face Osasuna on Wednesday night.
However, as reported by Marca, the Brazilian pulled up in training ahead of this fixture and will not be able to feature.
More worryingly, the report also claims that the knock will prevent Casemiro from featuring against City next Tuesday. Should the player not make the squad, Ancelotti has a big call to make in midfield.
Natural replacement Eduardo Camavinga lacks experience in games of this magnitude, but the Real boss will be reluctant to move Federico Valverde back into the middle of the park after he impressed in a right-forward berth against Chelsea in the quarter-finals.
Should he elect to shift Valverde back, Rodrygo – who has blown hot and cold this season – would likely be fielded on the right, though Gareth Bale and Marco Asensio are options too.
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Source : 90min