Anthony Joshua is often known for his calm and measured exterior before being released into the ring to do battle.

However, this control is not always easy to come by, particularly when it comes to trainer Rob McCracken.

McCracken, a former middleweight is regarded as being one of the most ferocious coaches in the world of boxing. He was instrumental in Joshua's Olympic success and is now looking to up the ante ahead of the highly anticipated clash between his protege and Wladimir Klitschko on April 29 at Wembley stadium.

The heavyweight from Watford has revealed that on occasion his discipline is pushed to the limit and he has occasionally considered allowing McCracken to feel the full force of one of his blows:

"When he is telling me I am doing things wrong, I want to give him a left hook to see if it is really that bad." Joshua said, as per The Sun.

Joshua, who says he is at his most vulnerable when tired, went on to add,

"He says it is bad and I am thinking, I want to miss the pad here and crack and see."

However, McCracken remains unscathed and this is what Joshua elects to focus on. He states that even if you feel you are about to lose your head, discipline is absolutely essential.

These will surely be comforting words for the Brummie taskmaster, although the IBF heavyweight world champion has revealed that his coach can take a punch.

In a recent sparring session with light-bantamweight world champion, Kal Yafai, the fellow Birmingham man caught his mentor with a mean right hand. While this would be enough to floor many, McCracken simply stood there and then continued with the session.

Joshua seems intent on remaining focused on his own preparations and believes Klitschko's attempts to unsettle him will not work:

"You really have to get under my skin to wind me up. It is a bit of an issue because I don’t want to get fines or bans."

This hard exterior will surely be difficult to penetrate both outside and inside the ring, even with a record as illustrious as Wladimir's.

One thing is certain, though. Do not get in the way of Anthony Joshua when he is tired.