Real Madrid have launched a staunch defence of captain Sergio Ramos after it was alleged he was involved in a breach of anti-doping regulations.

A report from Der Spiegel on Friday night said the Madrid captain returned a positive test for the glucocorticoid dexamethasone after the 2017 Champions League final in Cardiff, but that no action was taken as it was deemed to be due to an 'administrative mistake'.

The German magazine claims UEFA investigated but it was concluded that a doctor, not Ramos, was at fault for failing to declare dexamethasone's use. The substance is not banned if its use is declared.

And Madrid have backed Ramos, saying in a statement: "With regards to the reports published by Der Spiegel in relation to our captain, Sergio Ramos, the club wishes to express the following:

"Sergio Ramos has never breached anti-doping regulations.

"UEFA requested specific information and immediately closed the case referred to, as is customary in such instances, following tests carried out by experts from the World Anti-Doping Association (WADA) and UEFA itself."

The report went on to allege that doping control officers had been unable to work without obstruction when carrying out random tests on 10 Madrid players in February 2017.

On that, Madrid added: "In terms of the rest of the content published by the aforementioned publication, the club will not be making any comment, given the clearly insubstantial nature of the reports."

Madrid face Eibar in LaLiga on Saturday. UEFA has been contacted for comment.