Game of Thrones Hafthor Bjornsson shows off his impressive sparring skills in brutal session.

Bjornsson, who played the Mountain in HBO’s Game of Thrones, has a three-minute round with a man a few inches shorter than him.

The Icelander followed his partnered around the ring and used all of his 425lbs to annihilate his opponent during the early exchanges.

The fight started with Bjornsson chasing his opponent around the ring whilst landing vicious blow after blow.

However his stamina was questionable and he tired towards the end, this gave the other fighter an opportunity to get some hits in. 

When the fight ends, he collapsed to the ground through pure exhaustion.

Fighting fans all had their chance to comment on his performance, some were impressed with his raw power and saw potential if he was going to get some training.

One fan commented: "[He] is an elite athlete I’m sure if he had a real boxing coach he would do great after a lot of time and hard work."

Another, @MrGimmick77 argued: "As someone who practices Muay Thai, I can say with confidence that his lack of technique does not undermine his lethal reach, and power.

https://www.youtube.com/embed/23LR6pWEpKU

Literally the only things he's missing is speed, and skill, which is something anyone can develop

"This was basically two minutes of getting mauled by a bear." Another viewer commented. 

This isn’t the first time that the 6ft 9in actor has stepped in to the ring for a sparring session, in 2015 he jumped in to the ring with former UFC champion Conor McGregor. 

Footage from that session went viral and McGregor said at the time: 

“[I said,] 'Let's take a cool picture like that,'" he said at the time."

"We squared off as if we were gonna do it. Then all of a sudden, he's bouncing and I'm bouncing.

"Next thing you know, we're having a full bare-knuckle body shot fight.

"I was hitting him with some shots. had to hit him with some shots. He was trying to hit me as well.

"He wasn't taking it easy. He tried to grab me and tried to pull my head off. I defended, freed the head. I was like, this motherf****r is so big, I have to start smashing him to the body.'"