Barcelona has temporarily stripped goalkeeper Marc-Andre ter Stegen of the captaincy over his refusal to sign a medical report about his back injury.

Goalkeeper Marc-Andre ter Stegen took to social media on Friday to defend himself after Barcelona started disciplinary proceedings that could allow them to terminate his contract.

“In recent weeks, many things have been said about me – some of them entirely unfounded,” he wrote on Instagram. “Therefore, I feel it is necessary to express my version of events respectfully, yet clearly.”

The club started disciplinary action on Tuesday and stripped the German of the club captaincy on Thursday.

The dispute centres on the German’s fitness after he underwent back surgery at the end of July.