Wladimir Klitschko's manager Bernd Boente has revealed that his client would have been fit to face Anthony Joshua on December 10, despite the fight being postponed due to injury.

Joshua's promoter Eddie Hearn announced on Monday that the heavyweight showdown has been postponed until 2017 after Klitschko suffered a calf injury.

However, Boente has claimed that the decision to delay the fight was made due to the contract not yet being finalised.

"Wladimir suffered a strained muscle in the calf. It was nothing bad, but he needs to briefly pause [training] for a few days," The Mirror quotes Boente as saying.

"If we had already finished the fight contract, then he could have boxed in December. It is now better that Wladimir properly recovers."

Joshua stepped up to face the former WBA and WBO heavyweight champion after the Ukrainian's rematch with Tyson Fury was scrapped.