Barcelona have confirmed Lionel Messi is having kidney tests.
Messi missed the Club World Cup semi-final in December due to a renal colic, an abdominal ailment often related to the presence of kidney stones within renal ducts.
Barcelona says in a statement Monday that the tests to be conducted by Tuesday at the latest, are "to assess the evolution of the kidney problem he suffered last December."
The statement says Messi will resume training with the squad on Wednesday, when Barcelona travel to Valencia for the return leg of the Copa del Rey semi-finals - a tie they lead 7-0 lead.