Barcelona have confirmed that Lionel Messi has undergone further tests on kidney problems which first emerged in December.
The Argentina international missed part of the Club World Cup in Japan as a result of renal colic, an abdominal discomfort commonly caused by kidney stones.
Reports emerged in Spain on Monday suggesting Messi could face minor surgery in order to correct the problem, which is claimed has persisted in recent weeks despite the 28-year-old missing only one match in 2016 so far.
Barca have clarified that medical checks are due to take place over two days this week but expect the forward to return to team training on Wednesday.
"Leo Messi will be submitted for different tests on Monday and Tuesday to assess the development of the kidney problems suffered in December," a Barcelona statement read.
"On Wednesday the player will return to training with the first team."
Messi could well be rested for the Copa del Rey semi-final second leg with Valencia on Wednesday given that Barca hold a 7-0 aggregate lead.