Borussia Dortmund and Germany footballer Mario Gotze has been ruled out for an indefinite period with what is being described as "metabolic disturbances".
The Germany international has only played 24 minutes in the top flight Bundesliga in 2017 and just 16 times in all competitions this season after returning to the Dortmund after three underwhelming years at Bayern Munich following an acrimonious transfer that had been announced shortly before the all-German Champions League final between the sides.
The midfielder says he is undergoing treatment and is doing everything in his power to return as soon as possible.
"I'm currently being treated, and I'm going to give everything to get back to training as quickly as possible and help the team to reach our goals," the Dortmund academy graduate said.
It is just under three years since Gotze scored Germany's winning goal against Argentina in extra time in the 2014 World Cup final.
His club have said that his return to action will not be a short-term thing, although no exact timeframe has been given, with Dortmund looking to find the root cause of the muscular issues he has suffered in recent times.
"We're happy to have now uncovered the reasons for Mario's difficulties and are convinced that his extraordinary abilities will give us additional quality once he has completely recovered from this," said Michael Zorc, the club's sporting director.
"Mario has the full backing and maximum support of everyone at BVB during his recovery!"
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