Barcelona star Lionel Messi was forced to miss training on Monday due to a suspected recurrence of a kidney problem.
The news was confirmed in an official statement on the club website: "Barcelona striker Lionel Messi will undergo several tests on Monday and Tuesday to assess the evolution of the kidney problems he suffered last December.
"Messi will return to his normal duties with the first team on Wednesday."
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Back in December, Messi was forced to sit out of Barcelona's Fifa Club World Cup semi-final due to renal colic, a painful condition normally attributed to kidney stones.
In his absence, Barca prevailed 3-0 over Luiz Felipe Scolari's Guangzhou Evergrande, and coach Luis Enrique will not be in any rush to push Messi back into action.
Even if the Argentinian forward passes all the necessary tests, Enrique may well decide to rest his star player for Wednesday's fixture against Gary Neville's Valencia.
Going into the second leg of their Copa del Rey semi-final, Barcelona lead 7-0 thanks to a hat-trick from Messi, alongside four from former Liverpool striker Luis Suarez.
Instead, Messi could return for Sunday's home game against Celta Vigo as Enrique's side look to extend their lead at the top of La Liga.
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